diff options
Diffstat (limited to 'mcs')
-rw-r--r-- | mcs/class/Mono.C5/LICENSE.txt | 19 | ||||
-rw-r--r-- | mcs/class/Mono.C5/trees/RedBlackTreeBag.cs | 4295 |
2 files changed, 4314 insertions, 0 deletions
diff --git a/mcs/class/Mono.C5/LICENSE.txt b/mcs/class/Mono.C5/LICENSE.txt new file mode 100644 index 00000000000..495ee7c5e80 --- /dev/null +++ b/mcs/class/Mono.C5/LICENSE.txt @@ -0,0 +1,19 @@ +Copyright (c) 2003-2004 Niels Joergen Kokholm <kokholm@itu.dk>, Peter Sestoft <sestoft@dina.kvl.dk>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/mcs/class/Mono.C5/trees/RedBlackTreeBag.cs b/mcs/class/Mono.C5/trees/RedBlackTreeBag.cs new file mode 100644 index 00000000000..cd2518bc334 --- /dev/null +++ b/mcs/class/Mono.C5/trees/RedBlackTreeBag.cs @@ -0,0 +1,4295 @@ +/*
+ Copyright (c) 2003-2004 Niels Kokholm <kokholm@itu.dk> and Peter Sestoft <sestoft@dina.kvl.dk>
+ Permission is hereby granted, free of charge, to any person obtaining a copy
+ of this software and associated documentation files (the "Software"), to deal
+ in the Software without restriction, including without limitation the rights
+ to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ copies of the Software, and to permit persons to whom the Software is
+ furnished to do so, subject to the following conditions:
+
+ The above copyright notice and this permission notice shall be included in
+ all copies or substantial portions of the Software.
+
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ SOFTWARE.
+*/
+
+#define MAINTAIN_SIZE
+#define MAINTAIN_RANKnot
+#define MAINTAIN_HEIGHTnot
+#define BAG
+#define NCP
+
+#define MAINTAIN_EXTREMAnot
+#define TRACE_IDnot
+
+#if BAG
+#if !MAINTAIN_SIZE
+#error BAG defined without MAINTAIN_SIZE!
+#endif
+#endif
+
+
+using System;
+using MSG = System.Collections.Generic;
+
+// NOTE NOTE NOTE NOTE
+// This source file is used to produce both TreeBag<T> and TreeBag<T>
+// It should be copied to a file called TreeBag.cs in which all code mentions of
+// TreeBag is changed to TreeBag and the preprocessor symbol BAG is defined.
+// NOTE: there may be problems with documentation comments.
+
+namespace C5
+{
+#if BAG
+ /// <summary>
+ /// An implementation of Red-Black trees as an indexed, sorted collection with bag semantics,
+ /// cf. <a href="litterature.htm#CLRS">CLRS</a>. (<see cref="T:C5.TreeBag!1"/> for an
+ /// implementation with set semantics).
+ /// <br/>
+ /// The comparer (sorting order) may be either natural, because the item type is comparable
+ /// (generic: <see cref="T:C5.IComparable!1"/> or non-generic: System.IComparable) or it can
+ /// be external and supplied by the user in the constructor.
+ /// <br/>
+ /// Each distinct item is only kept in one place in the tree - together with the number
+ /// of times it is a member of the bag. Thus, if two items that are equal according
+ /// </summary>
+#else
+ /// <summary>
+ /// An implementation of Red-Black trees as an indexed, sorted collection with set semantics,
+ /// cf. <a href="litterature.htm#CLRS">CLRS</a>. <see cref="T:C5.TreeBag!1"/> for a version
+ /// with bag semantics. <see cref="T:C5.TreeDictionary!2"/> for a sorted dictionary
+ /// based on this tree implementation.
+ /// <p>
+ /// The comparer (sorting order) may be either natural, because the item type is comparable
+ /// (generic: <see cref="T:C5.IComparable!1"/> or non-generic: System.IComparable) or it can
+ /// be external and supplied by the user in the constructor.</p>
+ ///
+ /// <p><i>TODO: describe performance here</i></p>
+ /// <p><i>TODO: discuss persistence and its useful usage modes. Warn about the space
+ /// leak possible with other usage modes.</i></p>
+ /// </summary>
+#endif
+ public class TreeBag<T>: SequencedBase<T>, IIndexedSorted<T>, IPersistentSorted<T>
+ {
+ #region Feature
+ /// <summary>
+ /// A debugging aid for making the selected compilation alternatives
+ /// available to the user. (To be removed when selection is finally fixed
+ /// for production version).
+ /// </summary>
+ [Flags]
+ public enum Feature: short
+ {
+ /// <summary>
+ /// Nothing
+ /// </summary>
+ Dummy = 0,
+ /// <summary>
+ /// Node copy persistence as explained in <a href="litterature.htm#Tarjan1">Tarjan1</a>
+ /// </summary>
+ NodeCopyPersistence = 2,
+ /// <summary>
+ /// Maintain sub tree sizes
+ /// </summary>
+ Sizes = 4,
+ /// <summary>
+ /// Maintain precise node heights
+ /// </summary>
+ Heights = 8,
+ /// <summary>
+ /// Maintain node ranks (~ black height)
+ /// </summary>
+ Ranks = 16,
+ /// <summary>
+ /// Maintain unique ids on tree nodes.
+ /// </summary>
+ Traceid = 32
+ }
+
+
+
+ static Feature features = Feature.Dummy
+#if NCP
+ | Feature.NodeCopyPersistence
+#endif
+#if MAINTAIN_RANK
+ |Feature.Ranks
+#endif
+#if MAINTAIN_HEIGHT
+ |Feature.Heights
+#endif
+#if MAINTAIN_SIZE
+ | Feature.Sizes
+#endif
+#if TRACE_ID
+ | Feature.Traceid
+#endif
+ ;
+
+
+ /// <summary>
+ /// A debugging aid for making the selected compilation alternatives
+ /// available to the user. (To be removed when selection is finally fixed
+ /// for production version).
+ /// </summary>
+ public static Feature Features { get { return features; } }
+
+ #endregion
+
+ #region Fields
+
+ IComparer<T> comparer;
+
+ Node root;
+
+ int blackdepth = 0;
+
+ //We double these stacks for the iterative add and remove on demand
+ private int[] dirs = new int[2];
+
+ private Node[] path = new Node[2];
+#if NCP
+ private bool isSnapShot = false;
+
+ private SnapData snapdata;
+
+ private int generation;
+
+ private int maxsnapid = -1;
+
+#endif
+#if MAINTAIN_EXTREMA
+ T min, max;
+#endif
+#if MAINTAIN_HEIGHT
+ private short depth = 0;
+#endif
+ #endregion
+
+ #region Util
+
+ /// <summary>
+ /// Fetch the left child of n taking node-copying persistence into
+ /// account if relevant.
+ /// </summary>
+ /// <param name="n"></param>
+ /// <returns></returns>
+ private Node left(Node n)
+ {
+#if NCP
+ if (isSnapShot)
+ {
+#if SEPARATE_EXTRA
+ Node.Extra e = n.extra;
+
+ if (e != null && e.lastgeneration >= treegen && e.leftnode)
+ return e.oldref;
+#else
+ if (n.lastgeneration >= generation && n.leftnode)
+ return n.oldref;
+#endif
+ }
+#endif
+ return n.left;
+ }
+
+
+ private Node right(Node n)
+ {
+#if NCP
+ if (isSnapShot)
+ {
+#if SEPARATE_EXTRA
+ Node.Extra e = n.extra;
+
+ if (e != null && e.lastgeneration >= treegen && !e.leftnode)
+ return e.oldref;
+#else
+ if (n.lastgeneration >= generation && !n.leftnode)
+ return n.oldref;
+#endif
+ }
+#endif
+ return n.right;
+ }
+
+
+ //This method should be called by methods that use the internal
+ //traversal stack, unless certain that there is room enough
+ private void stackcheck()
+ {
+ while (dirs.Length < 2 * blackdepth)
+ {
+ dirs = new int[2 * dirs.Length];
+ path = new Node[2 * dirs.Length];
+ }
+ }
+
+ #endregion
+
+ #region Node nested class
+
+
+ /// <summary>
+ /// The type of node in a Red-Black binary tree
+ /// </summary>
+ class Node
+ {
+ public bool red = true;
+
+ public T item;
+
+ public Node left;
+
+ public Node right;
+
+#if MAINTAIN_SIZE
+ public int size = 1;
+#endif
+
+#if BAG
+ public int items = 1;
+#endif
+
+#if MAINTAIN_HEIGHT
+ public short height;
+#endif
+
+#if MAINTAIN_RANK
+ public short rank = 1;
+#endif
+
+#if TRACE_ID
+ public int id = sid++;
+ public static int sid = 0;
+#endif
+
+#if NCP
+ public int generation;
+#if SEPARATE_EXTRA
+ internal class Extra
+ {
+ public int lastgeneration;
+
+ public Node oldref;
+
+ public bool leftnode;
+
+ //public Node next;
+ }
+
+ public Extra extra;
+
+#else
+ public int lastgeneration = -1;
+
+ public Node oldref;
+
+ public bool leftnode;
+#endif
+
+ /// <summary>
+ /// Update a child pointer
+ /// </summary>
+ /// <param name="cursor"></param>
+ /// <param name="leftnode"></param>
+ /// <param name="child"></param>
+ /// <param name="maxsnapid"></param>
+ /// <param name="generation"></param>
+ /// <returns>True if node was *copied*</returns>
+ internal static bool update(ref Node cursor, bool leftnode, Node child, int maxsnapid, int generation)
+ {
+ Node oldref = leftnode ? cursor.left : cursor.right;
+
+ if (child == oldref)
+ return false;
+
+ bool retval = false;
+
+ if (cursor.generation <= maxsnapid)
+ {
+#if SEPARATE_EXTRA
+ if (cursor.extra == null)
+ {
+ Extra extra = cursor.extra = new Extra();
+
+ extra.leftnode = leftnode;
+ extra.lastgeneration = maxsnapid;
+ extra.oldref = oldref;
+ }
+ else if (cursor.extra.leftnode != leftnode || cursor.extra.lastgeneration < maxsnapid)
+#else
+ if (cursor.lastgeneration == -1)
+ {
+ cursor.leftnode = leftnode;
+ cursor.lastgeneration = maxsnapid;
+ cursor.oldref = oldref;
+ }
+ else if (cursor.leftnode != leftnode || cursor.lastgeneration < maxsnapid)
+#endif
+ {
+ CopyNode(ref cursor, maxsnapid, generation);
+ retval = true;
+ }
+ }
+
+ if (leftnode)
+ cursor.left = child;
+ else
+ cursor.right = child;
+
+ return retval;
+ }
+
+
+ //If cursor.extra.lastgeneration==maxsnapid, the extra pointer will
+ //always be used in the old copy of cursor. Therefore, after
+ //making the clone, we should update the old copy by restoring
+ //the child pointer and setting extra to null.
+ //OTOH then we cannot clean up unused Extra objects unless we link
+ //them together in a doubly linked list.
+ public static bool CopyNode(ref Node cursor, int maxsnapid, int generation)
+ {
+ if (cursor.generation <= maxsnapid)
+ {
+ cursor = (Node)(cursor.MemberwiseClone());
+ cursor.generation = generation;
+#if SEPARATE_EXTRA
+ cursor.extra = null;
+#else
+ cursor.lastgeneration = -1;
+#endif
+#if TRACE_ID
+ cursor.id = sid++;
+#endif
+ return true;
+ }
+ else
+ return false;
+ }
+
+#endif
+ }
+
+ #endregion
+
+ #region Constructors
+
+ /// <summary>
+ /// Create a red-black tree collection with natural comparer and item hasher.
+ /// </summary>
+ public TreeBag()
+ {
+ comparer = ComparerBuilder.FromComparable<T>.Examine();
+ itemhasher = HasherBuilder.ByPrototype<T>.Examine();
+ }
+
+
+ /// <summary>
+ /// Create a red-black tree collection with an external comparer (and natural item hasher,
+ /// assumed consistent).
+ /// </summary>
+ /// <param name="c">The external comparer</param>
+ public TreeBag(IComparer<T> c)
+ {
+ comparer = c;
+ itemhasher = HasherBuilder.ByPrototype<T>.Examine();
+ }
+
+
+ /// <summary>
+ /// Create a red-black tree collection with an external comparer aand an external
+ /// item hasher, assumed consistent.
+ /// </summary>
+ /// <param name="c">The external comparer</param>
+ /// <param name="h">The external item hasher</param>
+ public TreeBag(IComparer<T> c, IHasher<T> h)
+ {
+ comparer = c;
+ itemhasher = h;
+ }
+
+ #endregion
+
+ #region TreeBag.Enumerator nested class
+
+ /// <summary>
+ /// An enumerator for a red-black tree collection. Based on an explicit stack
+ /// of subtrees waiting to be enumerated. Currently only used for the tree set
+ /// enumerators (tree bag enumerators use an iterator block based enumerator).
+ /// </summary>
+ public class Enumerator: MSG.IEnumerator<T>
+ {
+ #region Private Fields
+ TreeBag<T> tree;
+
+ bool valid = false;
+
+ int stamp;
+
+ T current;
+
+ Node cursor;
+
+ Node[] path; // stack of nodes
+
+ int level = 0;
+ #endregion
+ /// <summary>
+ /// Create a tree enumerator
+ /// </summary>
+ /// <param name="tree">The red-black tree to enumerate</param>
+ public Enumerator(TreeBag<T> tree)
+ {
+ this.tree = tree;
+ stamp = tree.stamp;
+ path = new Node[2 * tree.blackdepth];
+ cursor = new Node();
+ cursor.right = tree.root;
+ }
+
+
+ /// <summary>
+ /// Undefined if enumerator is not valid (MoveNext hash been called returning true)
+ /// </summary>
+ /// <value>The current item of the enumerator.</value>
+ [Tested]
+ public T Current
+ {
+ [Tested]
+ get
+ {
+ if (valid)
+ return current;
+ else
+ throw new InvalidOperationException();
+ }
+ }
+
+
+ //Maintain a stack of nodes that are roots of
+ //subtrees not completely exported yet. Invariant:
+ //The stack nodes together with their right subtrees
+ //consists of exactly the items we have not passed
+ //yet (the top of the stack holds current item).
+ /// <summary>
+ /// Move enumerator to next item in tree, or the first item if
+ /// this is the first call to MoveNext.
+ /// <exception cref="InvalidOperationException"/> if underlying tree was modified.
+ /// </summary>
+ /// <returns>True if enumerator is valid now</returns>
+ [Tested]
+ public bool MoveNext()
+ {
+ tree.modifycheck(stamp);
+ if (cursor.right != null)
+ {
+ path[level] = cursor = cursor.right;
+ while (cursor.left != null)
+ path[++level] = cursor = cursor.left;
+ }
+ else if (level == 0)
+ return valid = false;
+ else
+ cursor = path[--level];
+
+ current = cursor.item;
+ return valid = true;
+ }
+
+
+ #region IDisposable Members for Enumerator
+
+ bool disposed;
+
+
+ /// <summary>
+ /// Call Dispose(true) and then suppress finalization of this enumerator.
+ /// </summary>
+ [Tested]
+ public void Dispose()
+ {
+ Dispose(true);
+ GC.SuppressFinalize(this);
+ }
+
+
+ /// <summary>
+ /// Remove the internal data (notably the stack array).
+ /// </summary>
+ /// <param name="disposing">True if called from Dispose(),
+ /// false if called from the finalizer</param>
+ protected virtual void Dispose(bool disposing)
+ {
+ if (!disposed)
+ {
+ if (disposing)
+ {
+ }
+
+ current = default(T);
+ cursor = null;
+ path = null;
+ disposed = true;
+ }
+ }
+
+
+ /// <summary>
+ /// Finalizer for enumeratir
+ /// </summary>
+ ~Enumerator()
+ {
+ Dispose(false);
+ }
+ #endregion
+
+ }
+#if NCP
+ /// <summary>
+ /// An enumerator for a snapshot of a node copy persistent red-black tree
+ /// collection.
+ /// </summary>
+ public class SnapEnumerator: MSG.IEnumerator<T>
+ {
+ #region Private Fields
+ TreeBag<T> tree;
+
+ bool valid = false;
+
+ int stamp;
+#if BAG
+ int togo;
+#endif
+
+ T current;
+
+ Node cursor;
+
+ Node[] path; // stack of nodes
+
+ int level;
+ #endregion
+
+ /// <summary>
+ /// Creta an enumerator for a snapshot of a node copy persistent red-black tree
+ /// collection
+ /// </summary>
+ /// <param name="tree">The snapshot</param>
+ public SnapEnumerator(TreeBag<T> tree)
+ {
+ this.tree = tree;
+ stamp = tree.stamp;
+ path = new Node[2 * tree.blackdepth];
+ cursor = new Node();
+ cursor.right = tree.root;
+ }
+
+
+ #region MSG.IEnumerator<T> Members
+
+ /// <summary>
+ /// Move enumerator to next item in tree, or the first item if
+ /// this is the first call to MoveNext.
+ /// <exception cref="InvalidOperationException"/> if underlying tree was modified.
+ /// </summary>
+ /// <returns>True if enumerator is valid now</returns>
+ [Tested]
+ public bool MoveNext()
+ {
+ tree.modifycheck(stamp);//???
+
+#if BAG
+ if (--togo>0)
+ return true;
+#endif
+ Node next = tree.right(cursor);
+
+ if (next != null)
+ {
+ path[level] = cursor = next;
+ next = tree.left(cursor);
+ while (next != null)
+ {
+ path[++level] = cursor = next;
+ next = tree.left(cursor);
+ }
+ }
+ else if (level == 0)
+ return valid = false;
+ else
+ cursor = path[--level];
+
+#if BAG
+ togo = cursor.items;
+#endif
+ current = cursor.item;
+ return valid = true;
+ }
+
+
+ /// <summary>
+ /// Undefined if enumerator is not valid (MoveNext hash been called returning true)
+ /// </summary>
+ /// <value>The current value of the enumerator.</value>
+ [Tested]
+ public T Current
+ {
+ [Tested]
+ get
+ {
+ if (valid)
+ return current;
+ else
+ throw new InvalidOperationException();
+ }
+ }
+
+ #endregion
+
+ #region IDisposable Members
+
+ [Tested]
+ void System.IDisposable.Dispose()
+ {
+ tree = null;
+ valid = false;
+ current = default(T);
+ cursor = null;
+ path = null;
+ }
+
+ #endregion
+ }
+#endif
+ #endregion
+
+ #region IEnumerable<T> Members
+
+ private MSG.IEnumerator<T> getEnumerator(Node node, int origstamp)
+ {
+ if (node == null)
+ yield break;
+
+ if (node.left != null)
+ {
+ MSG.IEnumerator<T> child = getEnumerator(node.left, origstamp);
+
+ while (child.MoveNext())
+ {
+ modifycheck(origstamp);
+ yield return child.Current;
+ }
+ }
+#if BAG
+ int togo = node.items;
+ while (togo-- > 0)
+ {
+ modifycheck(origstamp);
+ yield return node.item;
+ }
+#else
+ modifycheck(origstamp);
+ yield return node.item;
+#endif
+ if (node.right != null)
+ {
+ MSG.IEnumerator<T> child = getEnumerator(node.right, origstamp);
+
+ while (child.MoveNext())
+ {
+ modifycheck(origstamp);
+ yield return child.Current;
+ }
+ }
+ }
+
+
+ /// <summary>
+ /// Create an enumerator for this tree
+ /// </summary>
+ /// <returns>The enumerator</returns>
+ [Tested]
+ public override MSG.IEnumerator<T> GetEnumerator()
+ {
+#if NCP
+ if (isSnapShot)
+ return new SnapEnumerator(this);
+#endif
+#if BAG
+ return getEnumerator(root,stamp);
+#else
+ return new Enumerator(this);
+#endif
+ }
+
+ #endregion
+
+ #region ISink<T> Members
+
+ /// <summary>
+ /// Add item to tree. If already there, return the found item in the second argument.
+ /// </summary>
+ /// <param name="item">Item to add</param>
+ /// <param name="founditem">item found</param>
+ /// <param name="update">whether item in node should be updated</param>
+ /// <param name="wasfound">true if found in bag, false if not found or tre is a set</param>
+ /// <returns>True if item was added</returns>
+ bool addIterative(T item, ref T founditem, bool update, out bool wasfound)
+ {
+ wasfound = false;
+ if (root == null)
+ {
+ root = new Node();
+ root.red = false;
+ blackdepth = 1;
+#if MAINTAIN_EXTREMA
+ root.item = min = max = item;
+#else
+ root.item = item;
+#endif
+#if NCP
+ root.generation = generation;
+#endif
+#if MAINTAIN_HEIGHT
+ depth = 0;
+#endif
+ return true;
+ }
+
+ stackcheck();
+
+ int level = 0;
+ Node cursor = root;
+
+ while (true)
+ {
+ int comp = comparer.Compare(cursor.item, item);
+
+ if (comp == 0)
+ {
+ founditem = cursor.item;
+
+#if BAG
+ wasfound = true;
+#if NCP
+ Node.CopyNode(ref cursor, maxsnapid, generation);
+#endif
+ cursor.items++;
+ cursor.size++;
+ if (update)
+ cursor.item = item;
+
+ update = true;
+
+#else
+ if (update)
+ {
+#if NCP
+ Node.CopyNode(ref cursor, maxsnapid, generation);
+#endif
+ cursor.item = item;
+ }
+#endif
+
+ while (level-- > 0)
+ {
+ if (update)
+ {
+ Node kid = cursor;
+
+ cursor = path[level];
+#if NCP
+ Node.update(ref cursor, dirs[level] > 0, kid, maxsnapid, generation);
+#endif
+#if BAG
+ cursor.size++;
+#endif
+ }
+
+ path[level] = null;
+ }
+#if BAG
+ return true;
+#else
+ if (update)
+ root = cursor;
+
+ return false;
+#endif
+ }
+
+ //else
+ Node child = comp > 0 ? cursor.left : cursor.right;
+
+ if (child == null)
+ {
+ child = new Node();
+ child.item = item;
+#if NCP
+ child.generation = generation;
+ Node.update(ref cursor, comp > 0, child, maxsnapid, generation);
+#else
+ if (comp > 0) { cursor.left = child; }
+ else { cursor.right = child; }
+#endif
+#if MAINTAIN_SIZE
+ cursor.size++;
+#endif
+#if MAINTAIN_HEIGHT
+ fixheight(cursor);
+#endif
+ dirs[level] = comp;
+ break;
+ }
+ else
+ {
+ dirs[level] = comp;
+ path[level++] = cursor;
+ cursor = child;
+ }
+ }
+
+ //We have just added the red node child to "cursor"
+ while (cursor.red)
+ {
+ //take one step up:
+ Node child = cursor;
+
+ cursor = path[--level];
+ path[level] = null;
+#if NCP
+ Node.update(ref cursor, dirs[level] > 0, child, maxsnapid, generation);
+#endif
+#if MAINTAIN_SIZE
+ cursor.size++;
+#endif
+ int comp = dirs[level];
+ Node childsibling = comp > 0 ? cursor.right : cursor.left;
+
+ if (childsibling != null && childsibling.red)
+ {
+ //Promote
+#if MAINTAIN_RANK
+ cursor.rank++;
+#endif
+#if MAINTAIN_HEIGHT
+ fixheight(cursor);
+#endif
+ child.red = false;
+#if NCP
+ Node.update(ref cursor, comp < 0, childsibling, maxsnapid, generation);
+#endif
+ childsibling.red = false;
+
+ //color cursor red & take one step up the tree unless at root
+ if (level == 0)
+ {
+ root = cursor;
+ blackdepth++;
+ return true;
+ }
+ else
+ {
+ cursor.red = true;
+#if NCP
+ child = cursor;
+ cursor = path[--level];
+ Node.update(ref cursor, dirs[level] > 0, child, maxsnapid, generation);
+#endif
+ path[level] = null;
+#if MAINTAIN_SIZE
+ cursor.size++;
+#endif
+#if MAINTAIN_HEIGHT
+ fixheight(cursor);
+#endif
+ }
+ }
+ else
+ {
+ //ROTATE!!!
+ int childcomp = dirs[level + 1];
+
+ cursor.red = true;
+ if (comp > 0)
+ {
+ if (childcomp > 0)
+ {//zagzag
+#if NCP
+ Node.update(ref cursor, true, child.right, maxsnapid, generation);
+ Node.update(ref child, false, cursor, maxsnapid, generation);
+#else
+ cursor.left = child.right;
+ child.right = cursor;
+#endif
+ cursor = child;
+ }
+ else
+ {//zagzig
+ Node badgrandchild = child.right;
+#if NCP
+ Node.update(ref cursor, true, badgrandchild.right, maxsnapid, generation);
+ Node.update(ref child, false, badgrandchild.left, maxsnapid, generation);
+ Node.CopyNode(ref badgrandchild, maxsnapid, generation);
+#else
+ cursor.left = badgrandchild.right;
+ child.right = badgrandchild.left;
+#endif
+ badgrandchild.left = child;
+ badgrandchild.right = cursor;
+ cursor = badgrandchild;
+ }
+ }
+ else
+ {//comp < 0
+ if (childcomp < 0)
+ {//zigzig
+#if NCP
+ Node.update(ref cursor, false, child.left, maxsnapid, generation);
+ Node.update(ref child, true, cursor, maxsnapid, generation);
+#else
+ cursor.right = child.left;
+ child.left = cursor;
+#endif
+ cursor = child;
+ }
+ else
+ {//zigzag
+ Node badgrandchild = child.left;
+#if NCP
+ Node.update(ref cursor, false, badgrandchild.left, maxsnapid, generation);
+ Node.update(ref child, true, badgrandchild.right, maxsnapid, generation);
+ Node.CopyNode(ref badgrandchild, maxsnapid, generation);
+#else
+ cursor.right = badgrandchild.left;
+ child.left = badgrandchild.right;
+#endif
+ badgrandchild.right = child;
+ badgrandchild.left = cursor;
+ cursor = badgrandchild;
+ }
+ }
+
+ cursor.red = false;
+
+#if MAINTAIN_SIZE
+ Node n;
+
+#if BAG
+ n = cursor.right;
+ cursor.size = n.size = (n.left == null ? 0 : n.left.size) + (n.right == null ? 0 : n.right.size) + n.items;
+ n = cursor.left;
+ n.size = (n.left == null ? 0 : n.left.size) + (n.right == null ? 0 : n.right.size) + n.items;
+ cursor.size += n.size + cursor.items;
+#else
+ n = cursor.right;
+ cursor.size = n.size = (n.left == null ? 0 : n.left.size) + (n.right == null ? 0 : n.right.size) + 1;
+ n = cursor.left;
+ n.size = (n.left == null ? 0 : n.left.size) + (n.right == null ? 0 : n.right.size) + 1;
+ cursor.size += n.size + 1;
+#endif
+#endif
+#if MAINTAIN_HEIGHT
+ fixheight(cursor.right);
+ fixheight(cursor.left);
+ fixheight(cursor);
+#endif
+ if (level == 0)
+ {
+ root = cursor;
+ return true;
+ }
+ else
+ {
+ child = cursor;
+ cursor = path[--level];
+ path[level] = null;
+#if NCP
+ Node.update(ref cursor, dirs[level] > 0, child, maxsnapid, generation);
+#else
+ if (dirs[level] > 0)
+ cursor.left = child;
+ else
+ cursor.right = child;
+#endif
+#if MAINTAIN_SIZE
+ cursor.size++;
+#endif
+#if MAINTAIN_HEIGHT
+ fixheight(cursor);
+#endif
+ break;
+ }
+ }
+ }
+#if NCP
+ bool stillmore = true;
+#endif
+ while (level > 0)
+ {
+ Node child = cursor;
+
+ cursor = path[--level];
+ path[level] = null;
+#if NCP
+ if (stillmore)
+ stillmore = Node.update(ref cursor, dirs[level] > 0, child, maxsnapid, generation);
+#endif
+#if MAINTAIN_SIZE
+ cursor.size++;
+#endif
+#if MAINTAIN_HEIGHT
+ fixheight(cursor);
+#endif
+ }
+
+ root = cursor;
+ return true;
+ }
+
+
+ /// <summary>
+ /// Add an item to this collection if possible. If this collection has set
+ /// semantics, the item will be added if not already in the collection. If
+ /// bag semantics, the item will always be added.
+ /// </summary>
+ /// <param name="item">The item to add.</param>
+ /// <returns>True if item was added.</returns>
+ [Tested]
+ public bool Add(T item)
+ {
+ updatecheck();
+
+ //Note: blackdepth of the tree is set inside addIterative
+ T j = default(T);
+ bool tmp;
+
+ if (addIterative(item, ref j, false, out tmp))
+ {
+ size++;
+#if MAINTAIN_EXTREMA
+ if (Compare(item, min) < 0)
+ min = item;
+ else if (Compare(item, max) > 0)
+ max = item;
+#endif
+#if MAINTAIN_HEIGHT
+ depth = root.height;
+#endif
+ return true;
+ }
+ else
+ return false;
+ }
+
+
+ /// <summary>
+ /// Add the elements from another collection to this collection. If this
+ /// collection has set semantics, only items not already in the collection
+ /// will be added.
+ /// </summary>
+ /// <param name="items">The items to add.</param>
+ [Tested]
+ public void AddAll(MSG.IEnumerable<T> items)
+ {
+ int c = 0;
+ T j = default(T);
+ bool tmp;
+
+ updatecheck();
+ foreach (T i in items)
+ if (addIterative(i, ref j, false, out tmp)) c++;
+
+ size += c;
+ }
+
+ /// <summary>
+ /// Add the elements from another collection with a more specialized item type
+ /// to this collection. If this
+ /// collection has set semantics, only items not already in the collection
+ /// will be added.
+ /// </summary>
+ /// <typeparam name="U">The type of items to add</typeparam>
+ /// <param name="items">The items to add</param>
+ public void AddAll<U>(MSG.IEnumerable<U> items) where U : T
+ {
+ int c = 0;
+ T j = default(T);
+ bool tmp;
+
+ updatecheck();
+ foreach (T i in items)
+ if (addIterative(i, ref j, false, out tmp)) c++;
+
+ size += c;
+ }
+
+
+ /// <summary>
+ /// Add all the items from another collection with an enumeration order that
+ /// is increasing in the items. <para>The idea is that the implementation may use
+ /// a faster algorithm to merge the two collections.</para>
+ /// <exception cref="ArgumentException"/> if the enumerated items turns out
+ /// not to be in increasing order.
+ /// </summary>
+ /// <param name="items">The collection to add.</param>
+ [Tested]
+ public void AddSorted(MSG.IEnumerable<T> items)
+ {
+ if (size > 0)
+ AddAll(items);
+ else
+ {
+ updatecheck();
+ addSorted(items, true);
+ }
+ }
+
+ #region add-sorted helpers
+
+ //Create a RB tree from x+2^h-1 (x < 2^h, h>=1) nodes taken from a
+ //singly linked list of red nodes using only the right child refs.
+ //The x nodes at depth h+1 will be red, the rest black.
+ //(h is the blackdepth of the resulting tree)
+ static Node maketreer(ref Node rest, int blackheight, int maxred, int red)
+ {
+ if (blackheight == 1)
+ {
+ Node top = rest;
+
+ rest = rest.right;
+ if (red > 0)
+ {
+ top.right = null;
+ rest.left = top;
+ top = rest;
+#if BAG
+ top.size += top.left.size;
+#elif MAINTAIN_SIZE
+ top.size = 1 + red;
+#endif
+ rest = rest.right;
+ red--;
+ }
+
+ if (red > 0)
+ {
+#if BAG
+ top.size += rest.size;
+#endif
+ top.right = rest;
+ rest = rest.right;
+ top.right.right = null;
+ }
+ else
+ top.right = null;
+
+ top.red = false;
+ return top;
+ }
+ else
+ {
+ maxred >>=1;
+
+ int lred = red > maxred ? maxred : red;
+ Node left = maketreer(ref rest, blackheight - 1, maxred, lred);
+ Node top = rest;
+
+ rest = rest.right;
+ top.left = left;
+ top.red = false;
+#if MAINTAIN_RANK
+ top.rank = (short)blackheight;
+#endif
+ top.right = maketreer(ref rest, blackheight - 1, maxred, red - lred);
+#if BAG
+ top.size = top.items + top.left.size + top.right.size;
+#elif MAINTAIN_SIZE
+ top.size = (maxred << 1) - 1 + red;
+#endif
+ return top;
+ }
+ }
+
+
+ void addSorted(MSG.IEnumerable<T> items, bool safe)
+ {
+ MSG.IEnumerator<T> e = items.GetEnumerator();;
+ if (size > 0)
+ throw new ApplicationException("This can't happen");
+
+ if (!e.MoveNext())
+ return;
+
+ //To count theCollect
+ Node head = new Node(), tail = head;
+ int z = 1;
+ T lastitem = tail.item = e.Current;
+#if BAG
+ int ec=0;
+#endif
+
+ while (e.MoveNext())
+ {
+#if BAG
+ T thisitem = e.Current;
+ int comp = comparer.Compare(lastitem, thisitem);
+ if (comp>0)
+ throw new ArgumentException("Argument not sorted");
+ if (comp == 0)
+ {
+ tail.items++;
+ ec++;
+ }
+ else
+ {
+ tail.size = tail.items;
+ z++;
+ tail.right = new Node();
+ tail = tail.right;
+ lastitem = tail.item = thisitem;
+#if NCP
+ tail.generation = generation;
+#endif
+ }
+#else
+ z++;
+ tail.right = new Node();
+ tail = tail.right;
+ tail.item = e.Current;
+ if (safe)
+ {
+ if (comparer.Compare(lastitem, tail.item) >= 0)
+ throw new ArgumentException("Argument not sorted");
+
+ lastitem = tail.item;
+ }
+#if NCP
+ tail.generation = generation;
+#endif
+#endif
+ }
+#if BAG
+ tail.size = tail.items;
+#endif
+ int blackheight = 0, red = z, maxred = 1;
+
+ while (maxred <= red)
+ {
+ red -= maxred;
+ maxred <<= 1;
+ blackheight++;
+ }
+
+ root = TreeBag<T>.maketreer(ref head, blackheight, maxred, red);
+ blackdepth = blackheight;
+ size = z;
+#if BAG
+ size += ec;
+#endif
+ return;
+ }
+
+ #endregion
+
+#if BAG
+ /// <summary></summary>
+ /// <value>True since this collection has bag semantics.</value>
+ [Tested]
+ public bool AllowsDuplicates { [Tested]get { return true; } }
+#else
+ /// <summary></summary>
+ /// <value>False since this tree has set semantics.</value>
+ [Tested]
+ public bool AllowsDuplicates { [Tested]get { return false; } }
+#endif
+
+ #endregion
+
+ #region IEditableCollection<T> Members
+
+
+ /// <summary>
+ /// The value is symbolic indicating the type of asymptotic complexity
+ /// in terms of the size of this collection (worst-case or amortized as
+ /// relevant).
+ /// </summary>
+ /// <value>Speed.Log</value>
+ [Tested]
+ public Speed ContainsSpeed { [Tested]get { return Speed.Log; } }
+
+
+ [Tested]
+ int ICollection<T>.GetHashCode() { return unsequencedhashcode(); }
+
+
+ [Tested]
+ bool ICollection<T>.Equals(ICollection<T> that)
+ { return unsequencedequals(that); }
+
+
+ /// <summary>
+ /// Check if this collection contains (an item equivalent to according to the
+ /// itemhasher) a particular value.
+ /// </summary>
+ /// <param name="item">The value to check for.</param>
+ /// <returns>True if the items is in this collection.</returns>
+ [Tested]
+ public bool Contains(T item)
+ {
+ Node next; int comp = 0;
+
+ next = root;
+ while (next != null)
+ {
+ comp = comparer.Compare(next.item, item);
+ if (comp == 0)
+ return true;
+
+ next = comp < 0 ? right(next) : left(next);
+ }
+
+ return false;
+ }
+
+
+ //Variant for dictionary use
+ //Will return the actual matching item in the ref argument.
+ /// <summary>
+ /// Check if this collection contains an item equivalent according to the
+ /// itemhasher to a particular value. If so, return in the ref argument (a
+ /// binary copy of) the actual value found.
+ /// </summary>
+ /// <param name="item">The value to look for.</param>
+ /// <returns>True if the items is in this collection.</returns>
+ [Tested]
+ public bool Find(ref T item)
+ {
+ Node next; int comp = 0;
+
+ next = root;
+ while (next != null)
+ {
+ comp = comparer.Compare(next.item, item);
+ if (comp == 0)
+ {
+ item = next.item;
+ return true;
+ }
+
+ next = comp < 0 ? right(next) : left(next);
+ }
+
+ return false;
+ }
+
+
+ /// <summary>
+ /// Find or add the item to the tree. If the tree does not contain
+ /// an item equivalent to this item add it, else return the exisiting
+ /// one in the ref argument.
+ ///
+ /// </summary>
+ /// <param name="item"></param>
+ /// <returns>True if item was found</returns>
+ [Tested]
+ public bool FindOrAdd(ref T item)
+ {
+ updatecheck();
+ bool wasfound;
+
+ //Note: blackdepth of the tree is set inside addIterative
+ if (addIterative(item, ref item, false, out wasfound))
+ {
+ size++;
+#if MAINTAIN_EXTREMA
+ if (Compare(item, min) < 0)
+ min = item;
+ else if (Compare(item, max) > 0)
+ max = item;
+#endif
+#if MAINTAIN_HEIGHT
+ depth = root.height;
+#endif
+ return wasfound;
+ }
+ else
+ return true;
+
+ }
+
+
+ //For dictionary use.
+ //If found, the matching entry will be updated with the new item.
+ /// <summary>
+ /// Check if this collection contains an item equivalent according to the
+ /// itemhasher to a particular value. If so, update the item in the collection
+ /// to with a binary copy of the supplied value. If the collection has bag semantics,
+ /// this updates all equivalent copies in
+ /// the collection.
+ /// </summary>
+ /// <param name="item">Value to update.</param>
+ /// <returns>True if the item was found and hence updated.</returns>
+ [Tested]
+ public bool Update(T item)
+ {
+ updatecheck();
+#if NCP
+ stackcheck();
+
+ int level = 0;
+#endif
+ Node cursor = root;
+ int comp = 0;
+
+ while (cursor != null)
+ {
+ comp = comparer.Compare(cursor.item, item);
+ if (comp == 0)
+ {
+#if NCP
+ Node.CopyNode(ref cursor, maxsnapid, generation);
+#endif
+ cursor.item = item;
+#if NCP
+ while (level > 0)
+ {
+ Node child = cursor;
+
+ cursor = path[--level];
+ path[level] = null;
+#if NCP
+ Node.update(ref cursor, dirs[level] > 0, child, maxsnapid, generation);
+#else
+ if (Node.CopyNode(maxsnapid, ref cursor, generation))
+ {
+ if (dirs[level] > 0)
+ cursor.left = child;
+ else
+ cursor.right = child;
+ }
+#endif
+ }
+
+ root = cursor;
+#endif
+ return true;
+ }
+#if NCP
+ dirs[level] = comp;
+ path[level++] = cursor;
+#endif
+ cursor = comp < 0 ? cursor.right : cursor.left;
+ }
+
+ return false;
+ }
+
+
+ /// <summary>
+ /// Check if this collection contains an item equivalent according to the
+ /// itemhasher to a particular value. If so, update the item in the collection
+ /// to with a binary copy of the supplied value; else add the value to the collection.
+ ///
+ /// <p>NOTE: the bag implementation is currently wrong!</p>
+ /// </summary>
+ /// <param name="item">Value to add or update.</param>
+ /// <returns>True if the item was found and updated (hence not added).</returns>
+ [Tested]
+ public bool UpdateOrAdd(T item)
+ {
+ updatecheck();
+ bool wasfound;
+
+ //Note: blackdepth of the tree is set inside addIterative
+ if (addIterative(item, ref item, true, out wasfound))
+ {
+ size++;
+#if MAINTAIN_EXTREMA
+ if (Compare(item, min) < 0)
+ min = item;
+ else if (Compare(item, max) > 0)
+ max = item;
+#endif
+#if MAINTAIN_HEIGHT
+ depth = root.height;
+#endif
+ return wasfound;
+ }
+ else
+ return true;
+ }
+
+
+ /// <summary>
+ /// Remove a particular item from this collection. If the collection has bag
+ /// semantics only one copy equivalent to the supplied item is removed.
+ /// </summary>
+ /// <param name="item">The value to remove.</param>
+ /// <returns>True if the item was found (and removed).</returns>
+ [Tested]
+ public bool Remove(T item)
+ {
+ updatecheck();
+ if (root == null)
+ return false;
+
+ return removeIterative(ref item, false);
+ }
+
+ /// <summary>
+ /// Remove a particular item from this collection if found. If the collection
+ /// has bag semantics only one copy equivalent to the supplied item is removed,
+ /// which one is implementation dependent.
+ /// If an item was removed, report a binary copy of the actual item removed in
+ /// the argument.
+ /// </summary>
+ /// <param name="item">The value to remove on input.</param>
+ /// <returns>True if the item was found (and removed).</returns>
+ [Tested]
+ public bool RemoveWithReturn(ref T item)
+ {
+ updatecheck();
+ if (root == null)
+ return false;
+
+ return removeIterative(ref item, false);
+ }
+
+
+ private bool removeIterative(ref T item, bool all)
+ {
+ //Stage 1: find item
+ stackcheck();
+
+ int level = 0, comp;
+ Node cursor = root;
+
+ while (true)
+ {
+ comp = comparer.Compare(cursor.item, item);
+ if (comp == 0)
+ {
+ item = cursor.item;
+#if BAG
+ if (!all && cursor.items > 1)
+ {
+#if NCP
+ Node.CopyNode(ref cursor, maxsnapid, generation);
+#endif
+ cursor.items--;
+ cursor.size--;
+ while (level-- > 0)
+ {
+ Node kid = cursor;
+
+ cursor = path[level];
+#if NCP
+ Node.update(ref cursor, dirs[level] > 0, kid,maxsnapid,generation);
+#endif
+ cursor.size--;
+ path[level] = null;
+ }
+ size--;
+ return true;
+ }
+#endif
+ break;
+ }
+
+ Node child = comp > 0 ? cursor.left : cursor.right;
+
+ if (child == null)
+ return false;
+
+ dirs[level] = comp;
+ path[level++] = cursor;
+ cursor = child;
+ }
+
+ return removeIterativePhase2(cursor, level);
+ }
+
+
+ private bool removeIterativePhase2(Node cursor, int level)
+ {
+ if (size == 1)
+ {
+ clear();
+ return true;
+ }
+
+#if MAINTAIN_EXTREMA
+ if (Compare(cursor.item, min) == 0)
+ min = cursor.right != null ? cursor.right.item : path[level - 1].item;
+ else if (Compare(cursor.item, max) == 0)
+ max = cursor.left != null ? cursor.left.item : path[level - 1].item;
+#endif
+#if BAG
+ int removedcount = cursor.items;
+ size -= removedcount;
+#else
+ //We are certain to remove one node:
+ size--;
+#endif
+ //Stage 2: if item's node has no null child, find predecessor
+ int level_of_item = level;
+
+ if (cursor.left != null && cursor.right != null)
+ {
+ dirs[level] = 1;
+ path[level++] = cursor;
+ cursor = cursor.left;
+ while (cursor.right != null)
+ {
+ dirs[level] = -1;
+ path[level++] = cursor;
+ cursor = cursor.right;
+ }
+#if NCP
+ Node.CopyNode(ref path[level_of_item], maxsnapid, generation);
+#endif
+ path[level_of_item].item = cursor.item;
+#if BAG
+ path[level_of_item].items = cursor.items;
+#endif
+ }
+
+ //Stage 3: splice out node to be removed
+ Node newchild = cursor.right == null ? cursor.left : cursor.right;
+ bool demote_or_rotate = newchild == null && !cursor.red;
+
+ //assert newchild.red
+ if (newchild != null)
+ {
+ newchild.red = false;
+ }
+
+ if (level == 0)
+ {
+ root = newchild;
+#if MAINTAIN_HEIGHT
+ depth = 0;
+#endif
+ return true;
+ }
+
+ level--;
+ cursor = path[level];
+ path[level] = null;
+
+ int comp = dirs[level];
+ Node childsibling;
+#if NCP
+ Node.update(ref cursor, comp > 0, newchild, maxsnapid, generation);
+#else
+ if (comp > 0)
+ cursor.left = newchild;
+ else
+ cursor.right = newchild;
+#endif
+ childsibling = comp > 0 ? cursor.right : cursor.left;
+#if BAG
+ cursor.size -= removedcount;
+#elif MAINTAIN_SIZE
+ cursor.size--;
+#endif
+#if MAINTAIN_HEIGHT
+ fixheight(cursor);
+#endif
+
+ //Stage 4: demote till we must rotate
+ Node farnephew = null, nearnephew = null;
+
+ while (demote_or_rotate)
+ {
+ if (childsibling.red)
+ break; //rotate 2+?
+
+ farnephew = comp > 0 ? childsibling.right : childsibling.left;
+ if (farnephew != null && farnephew.red)
+ break; //rotate 1b
+
+ nearnephew = comp > 0 ? childsibling.left : childsibling.right;
+ if (nearnephew != null && nearnephew.red)
+ break; //rotate 1c
+
+ //demote cursor
+ childsibling.red = true;
+#if MAINTAIN_RANK
+ cursor.rank--;
+#endif
+ if (level == 0)
+ {
+ cursor.red = false;
+ blackdepth--;
+#if MAINTAIN_HEIGHT
+ depth = root.height;
+#endif
+#if NCP
+ root = cursor;
+#endif
+ return true;
+ }
+ else if (cursor.red)
+ {
+ cursor.red = false;
+ demote_or_rotate = false;
+ break; //No rotation
+ }
+ else
+ {
+ Node child = cursor;
+
+ cursor = path[--level];
+ path[level] = null;
+ comp = dirs[level];
+ childsibling = comp > 0 ? cursor.right : cursor.left;
+#if NCP
+ Node.update(ref cursor, comp > 0, child, maxsnapid, generation);
+#endif
+#if BAG
+ cursor.size -= removedcount;
+#elif MAINTAIN_SIZE
+ cursor.size--;
+#endif
+#if MAINTAIN_HEIGHT
+ fixheight(cursor);
+#endif
+ }
+ }
+
+ //Stage 5: rotate
+ if (demote_or_rotate)
+ {
+ //At start:
+ //parent = cursor (temporary for swapping nodes)
+ //childsibling is the sibling of the updated child (x)
+ //cursor is always the top of the subtree
+ Node parent = cursor;
+
+ if (childsibling.red)
+ {//Case 2 and perhaps more.
+ //The y.rank == px.rank >= x.rank+2 >=2 so both nephews are != null
+ //(and black). The grandnephews are children of nearnephew
+ Node neargrandnephew, fargrandnephew;
+
+ if (comp > 0)
+ {
+ nearnephew = childsibling.left;
+ farnephew = childsibling.right;
+ neargrandnephew = nearnephew.left;
+ fargrandnephew = nearnephew.right;
+ }
+ else
+ {
+ nearnephew = childsibling.right;
+ farnephew = childsibling.left;
+ neargrandnephew = nearnephew.right;
+ fargrandnephew = nearnephew.left;
+ }
+
+ if (fargrandnephew != null && fargrandnephew.red)
+ {//Case 2+1b
+#if NCP
+ Node.CopyNode(ref nearnephew, maxsnapid, generation);
+
+ //The end result of this will always be e copy of parent
+ Node.update(ref parent, comp < 0, neargrandnephew, maxsnapid, generation);
+ Node.update(ref childsibling, comp > 0, nearnephew, maxsnapid, generation);
+#endif
+ if (comp > 0)
+ {
+ nearnephew.left = parent;
+ parent.right = neargrandnephew;
+ }
+ else
+ {
+ nearnephew.right = parent;
+ parent.left = neargrandnephew;
+ }
+
+ cursor = childsibling;
+ childsibling.red = false;
+ nearnephew.red = true;
+ fargrandnephew.red = false;
+#if MAINTAIN_RANK
+ nearnephew.rank++;
+ parent.rank--;
+#endif
+#if BAG
+ cursor.size = parent.size;
+ nearnephew.size = cursor.size - cursor.items - farnephew.size;
+ parent.size = nearnephew.size - nearnephew.items - fargrandnephew.size;
+#elif MAINTAIN_SIZE
+ cursor.size = parent.size;
+ nearnephew.size = cursor.size - 1 - farnephew.size;
+ parent.size = nearnephew.size - 1 - fargrandnephew.size;
+#endif
+#if MAINTAIN_HEIGHT
+ fixheight(parent);
+ fixheight(nearnephew);
+ fixheight(cursor);
+#endif
+ }
+ else if (neargrandnephew != null && neargrandnephew.red)
+ {//Case 2+1c
+#if NCP
+ Node.CopyNode(ref neargrandnephew, maxsnapid, generation);
+#endif
+ if (comp > 0)
+ {
+#if NCP
+ Node.update(ref childsibling, true, neargrandnephew, maxsnapid, generation);
+ Node.update(ref nearnephew, true, neargrandnephew.right, maxsnapid, generation);
+ Node.update(ref parent, false, neargrandnephew.left, maxsnapid, generation);
+#else
+ childsibling.left = neargrandnephew;
+ nearnephew.left = neargrandnephew.right;
+ parent.right = neargrandnephew.left;
+#endif
+ neargrandnephew.left = parent;
+ neargrandnephew.right = nearnephew;
+ }
+ else
+ {
+#if NCP
+ Node.update(ref childsibling, false, neargrandnephew, maxsnapid, generation);
+ Node.update(ref nearnephew, false, neargrandnephew.left, maxsnapid, generation);
+ Node.update(ref parent, true, neargrandnephew.right, maxsnapid, generation);
+#else
+ childsibling.right = neargrandnephew;
+ nearnephew.right = neargrandnephew.left;
+ parent.left = neargrandnephew.right;
+#endif
+ neargrandnephew.right = parent;
+ neargrandnephew.left = nearnephew;
+ }
+
+ cursor = childsibling;
+ childsibling.red = false;
+#if MAINTAIN_RANK
+ neargrandnephew.rank++;
+ parent.rank--;
+#endif
+#if BAG
+ cursor.size = parent.size;
+ parent.size = parent.items + (parent.left == null ? 0 : parent.left.size) + (parent.right == null ? 0 : parent.right.size);
+ nearnephew.size = nearnephew.items + (nearnephew.left == null ? 0 : nearnephew.left.size) + (nearnephew.right == null ? 0 : nearnephew.right.size);
+ neargrandnephew.size = neargrandnephew.items + parent.size + nearnephew.size;
+#elif MAINTAIN_SIZE
+ cursor.size = parent.size;
+ parent.size = 1 + (parent.left == null ? 0 : parent.left.size) + (parent.right == null ? 0 : parent.right.size);
+ nearnephew.size = 1 + (nearnephew.left == null ? 0 : nearnephew.left.size) + (nearnephew.right == null ? 0 : nearnephew.right.size);
+ neargrandnephew.size = 1 + parent.size + nearnephew.size;
+#endif
+#if MAINTAIN_HEIGHT
+ fixheight(parent);
+ fixheight(nearnephew);
+ fixheight(neargrandnephew);
+ fixheight(cursor);
+#endif
+ }
+ else
+ {//Case 2 only
+#if NCP
+ Node.update(ref parent, comp < 0, nearnephew, maxsnapid, generation);
+ Node.update(ref childsibling, comp > 0, parent, maxsnapid, generation);
+#else
+ if (comp > 0)
+ {
+ childsibling.left = parent;
+ parent.right = nearnephew;
+ }
+ else
+ {
+ childsibling.right = parent;
+ parent.left = nearnephew;
+ }
+#endif
+ cursor = childsibling;
+ childsibling.red = false;
+ nearnephew.red = true;
+#if MAINTAIN_RANK
+ parent.rank--;
+#endif
+#if BAG
+ cursor.size = parent.size;
+ parent.size -= farnephew.size + cursor.items;
+#elif MAINTAIN_SIZE
+ cursor.size = parent.size;
+ parent.size -= farnephew.size + 1;
+#endif
+#if MAINTAIN_HEIGHT
+ fixheight(parent);
+ fixheight(cursor);
+#endif
+ }
+ }
+ else if (farnephew != null && farnephew.red)
+ {//Case 1b
+ nearnephew = comp > 0 ? childsibling.left : childsibling.right;
+#if NCP
+ Node.update(ref parent, comp < 0, nearnephew, maxsnapid, generation);
+ Node.CopyNode(ref childsibling, maxsnapid, generation);
+ if (comp > 0)
+ {
+ childsibling.left = parent;
+ childsibling.right = farnephew;
+ }
+ else
+ {
+ childsibling.right = parent;
+ childsibling.left = farnephew;
+ }
+#else
+ if (comp > 0)
+ {
+ childsibling.left = parent;
+ parent.right = nearnephew;
+ }
+ else
+ {
+ childsibling.right = parent;
+ parent.left = nearnephew;
+ }
+#endif
+ cursor = childsibling;
+ cursor.red = parent.red;
+ parent.red = false;
+ farnephew.red = false;
+
+#if MAINTAIN_RANK
+ childsibling.rank++;
+ parent.rank--;
+#endif
+#if BAG
+ cursor.size = parent.size;
+ parent.size -= farnephew.size + cursor.items;
+#elif MAINTAIN_SIZE
+ cursor.size = parent.size;
+ parent.size -= farnephew.size + 1;
+#endif
+#if MAINTAIN_HEIGHT
+ fixheight(parent);
+ fixheight(cursor);
+#endif
+ }
+ else if (nearnephew != null && nearnephew.red)
+ {//Case 1c
+#if NCP
+ Node.CopyNode(ref nearnephew, maxsnapid, generation);
+#endif
+ if (comp > 0)
+ {
+#if NCP
+ Node.update(ref childsibling, true, nearnephew.right, maxsnapid, generation);
+ Node.update(ref parent, false, nearnephew.left, maxsnapid, generation);
+#else
+ childsibling.left = nearnephew.right;
+ parent.right = nearnephew.left;
+#endif
+ nearnephew.left = parent;
+ nearnephew.right = childsibling;
+ }
+ else
+ {
+#if NCP
+ Node.update(ref childsibling, false, nearnephew.left, maxsnapid, generation);
+ Node.update(ref parent, true, nearnephew.right, maxsnapid, generation);
+#else
+ childsibling.right = nearnephew.left;
+ parent.left = nearnephew.right;
+#endif
+ nearnephew.right = parent;
+ nearnephew.left = childsibling;
+ }
+
+ cursor = nearnephew;
+ cursor.red = parent.red;
+ parent.red = false;
+#if MAINTAIN_RANK
+ nearnephew.rank++;
+ parent.rank--;
+#endif
+#if BAG
+ cursor.size = parent.size;
+ parent.size = parent.items + (parent.left == null ? 0 : parent.left.size) + (parent.right == null ? 0 : parent.right.size);
+ childsibling.size = childsibling.items + (childsibling.left == null ? 0 : childsibling.left.size) + (childsibling.right == null ? 0 : childsibling.right.size);
+#elif MAINTAIN_SIZE
+ cursor.size = parent.size;
+ parent.size = 1 + (parent.left == null ? 0 : parent.left.size) + (parent.right == null ? 0 : parent.right.size);
+ childsibling.size = 1 + (childsibling.left == null ? 0 : childsibling.left.size) + (childsibling.right == null ? 0 : childsibling.right.size);
+#endif
+#if MAINTAIN_HEIGHT
+ fixheight(parent);
+ fixheight(childsibling);
+ fixheight(cursor);
+#endif
+ }
+ else
+ {//Case 1a can't happen
+ throw new Exception("Case 1a can't happen here");
+ }
+
+ //Resplice cursor:
+ if (level == 0)
+ {
+ root = cursor;
+ }
+ else
+ {
+ Node swap = cursor;
+
+ cursor = path[--level];
+ path[level] = null;
+#if NCP
+ Node.update(ref cursor, dirs[level] > 0, swap, maxsnapid, generation);
+#else
+
+ if (dirs[level] > 0)
+ cursor.left = swap;
+ else
+ cursor.right = swap;
+#endif
+#if BAG
+ cursor.size -= removedcount;
+#elif MAINTAIN_SIZE
+ cursor.size--;
+#endif
+#if MAINTAIN_HEIGHT
+ fixheight(cursor);
+#endif
+ }
+ }
+
+ //Stage 6: fixup to the root
+ while (level > 0)
+ {
+ Node child = cursor;
+
+ cursor = path[--level];
+ path[level] = null;
+#if NCP
+ if (child != (dirs[level] > 0 ? cursor.left : cursor.right))
+ Node.update(ref cursor, dirs[level] > 0, child, maxsnapid, generation);
+#endif
+#if BAG
+ cursor.size -= removedcount;
+#elif MAINTAIN_SIZE
+ cursor.size--;
+#endif
+#if MAINTAIN_HEIGHT
+ fixheight(cursor);
+#endif
+ }
+
+#if MAINTAIN_HEIGHT
+ depth = root.height;
+#endif
+#if NCP
+ root = cursor;
+#endif
+ return true;
+ }
+
+
+ /// <summary>
+ /// Remove all items from this collection.
+ /// </summary>
+ [Tested]
+ public void Clear()
+ {
+ updatecheck();
+ clear();
+ }
+
+
+ private void clear()
+ {
+ size = 0;
+ root = null;
+ blackdepth = 0;
+#if MAINTAIN_HEIGHT
+ depth = 0;
+#endif
+ }
+
+
+ /// <summary>
+ /// Remove all items in another collection from this one. If this collection
+ /// has bag semantics, take multiplicities into account.
+ /// </summary>
+ /// <param name="items">The items to remove.</param>
+ [Tested]
+ public void RemoveAll(MSG.IEnumerable<T> items)
+ {
+ updatecheck();
+
+ T jtem;
+
+ foreach (T item in items)
+ {
+ if (root == null)
+ break;
+
+ jtem = item;
+ removeIterative(ref jtem, false);
+ }
+ }
+
+
+ /// <summary>
+ /// Remove all items not in some other collection from this one. If this collection
+ /// has bag semantics, take multiplicities into account.
+ /// </summary>
+ /// <param name="items">The items to retain.</param>
+ [Tested]
+ public void RetainAll(MSG.IEnumerable<T> items)
+ {
+ updatecheck();
+
+ //A much more efficient version is possible if items is sorted like this.
+ //Well, it is unclear how efficient it would be.
+ //We could use a marking method!?
+ TreeBag<T> t = (TreeBag<T>)MemberwiseClone();
+
+ t.Clear();
+ foreach (T item in items)
+ if (ContainsCount(item) > t.ContainsCount(item))
+ t.Add(item);
+
+ root = t.root;
+ size = t.size;
+ blackdepth = t.blackdepth;
+#if MAINTAIN_HEIGHT
+ depth = t.depth;
+#endif
+ }
+
+
+ /// <summary>
+ /// Check if this collection contains all the values in another collection.
+ /// If this collection has bag semantics (<code>NoDuplicates==false</code>)
+ /// the check is made with respect to multiplicities, else multiplicities
+ /// are not taken into account.
+ /// </summary>
+ /// <param name="items">The </param>
+ /// <returns>True if all values in <code>items</code>is in this collection.</returns>
+ [Tested]
+ public bool ContainsAll(MSG.IEnumerable<T> items)
+ {
+ //This is worst-case O(m*logn)
+ foreach (T item in items)
+ if (!Contains(item)) return false;
+
+ return true;
+ }
+
+
+ //Higher order:
+ /// <summary>
+ /// Create a new indexed sorted collection consisting of the items of this
+ /// indexed sorted collection satisfying a certain predicate.
+ /// </summary>
+ /// <param name="filter">The filter delegate defining the predicate.</param>
+ /// <returns>The new indexed sorted collection.</returns>
+ [Tested]
+ public IIndexedSorted<T> FindAll(Filter<T> filter)
+ {
+ TreeBag<T> res = new TreeBag<T>(comparer);
+ MSG.IEnumerator<T> e = GetEnumerator();
+ Node head = null, tail = null;
+ int z = 0;
+#if BAG
+ int ec = 0;
+#endif
+ while (e.MoveNext())
+ {
+ T thisitem = e.Current;
+#if BAG
+ //We could document that filter will only be called
+ //once on each unique item. That might even be good for the user!
+ if (tail!=null && comparer.Compare(thisitem, tail.item) == 0)
+ {
+ tail.items++;
+ ec++;
+ continue;
+ }
+#endif
+ if (filter(thisitem))
+ {
+ if (head == null)
+ {
+ head = tail = new Node();
+ }
+ else
+ {
+#if BAG
+ tail.size = tail.items;
+#endif
+ tail.right = new Node();
+ tail = tail.right;
+ }
+
+ tail.item = thisitem;
+ z++;
+ }
+ }
+#if BAG
+ if (tail!=null)
+ tail.size = tail.items;
+#endif
+
+ if (z == 0)
+ return res;
+
+ int blackheight = 0, red = z, maxred = 1;
+
+ while (maxred <= red)
+ {
+ red -= maxred;
+ maxred <<= 1;
+ blackheight++;
+ }
+
+ res.root = TreeBag<T>.maketreer(ref head, blackheight, maxred, red);
+ res.blackdepth = blackheight;
+ res.size = z;
+#if BAG
+ res.size += ec;
+#endif
+ return res;
+ }
+
+
+ /// <summary>
+ /// Create a new indexed sorted collection consisting of the results of
+ /// mapping all items of this list.
+ /// <exception cref="ArgumentException"/> if the map is not increasing over
+ /// the items of this collection (with respect to the two given comparison
+ /// relations).
+ /// </summary>
+ /// <param name="mapper">The delegate definging the map.</param>
+ /// <param name="c">The comparion relation to use for the result.</param>
+ /// <returns>The new sorted collection.</returns>
+ [Tested]
+ public IIndexedSorted<V> Map<V>(Mapper<T,V> mapper, IComparer<V> c)
+ {
+ TreeBag<V> res = new TreeBag<V>(c);
+
+ if (size == 0)
+ return res;
+
+ MSG.IEnumerator<T> e = GetEnumerator();
+ TreeBag<V>.Node head = null, tail = null;
+ V oldv = default(V);
+ int z = 0;
+#if BAG
+ T lastitem = default(T);
+#endif
+ while (e.MoveNext())
+ {
+ T thisitem = e.Current;
+#if BAG
+ //We could document that mapper will only be called
+ //once on each unique item. That might even be good for the user!
+ if (tail != null && comparer.Compare(thisitem, lastitem) == 0)
+ {
+ tail.items++;
+ continue;
+ }
+#endif
+ V newv = mapper(thisitem);
+
+ if (head == null)
+ {
+ head = tail = new TreeBag<V>.Node();
+ z++;
+ }
+ else
+ {
+ int comp = c.Compare(oldv, newv);
+#if BAG
+ if (comp == 0)
+ {
+ tail.items++;
+ continue;
+ }
+ if (comp > 0)
+#else
+ if (comp >= 0)
+#endif
+ throw new ArgumentException("mapper not monotonic");
+#if BAG
+ tail.size = tail.items;
+#endif
+ tail.right = new TreeBag<V>.Node();
+ tail = tail.right;
+ z++;
+ }
+#if BAG
+ lastitem = thisitem;
+#endif
+ tail.item = oldv = newv;
+ }
+
+#if BAG
+ tail.size = tail.items;
+#endif
+
+ int blackheight = 0, red = z, maxred = 1;
+
+ while (maxred <= red)
+ {
+ red -= maxred;
+ maxred <<= 1;
+ blackheight++;
+ }
+
+ res.root = TreeBag<V>.maketreer(ref head, blackheight, maxred, red);
+ res.blackdepth = blackheight;
+ res.size = size;
+ return res;
+ }
+
+
+ //below is the bag utility stuff
+ /// <summary>
+ /// Count the number of items of the collection equal to a particular value.
+ /// Returns 0 if and only if the value is not in the collection.
+ /// </summary>
+ /// <param name="item">The value to count.</param>
+ /// <returns>The number of copies found.</returns>
+ [Tested]
+ public int ContainsCount(T item)
+ {
+#if BAG
+ Node next; int comp = 0;
+
+ next = root;
+ while (next != null)
+ {
+ comp = comparer.Compare(next.item, item);
+ if (comp == 0)
+ return next.items;
+
+ next = comp < 0 ? right(next) : left(next);
+ }
+
+ return 0;
+#else
+ //Since we are strictly NoDuplicates we just do
+ return Contains(item) ? 1 : 0;
+#endif
+ }
+
+
+ /// <summary>
+ /// Remove all items equivalent to a given value.
+ /// </summary>
+ /// <param name="item">The value to remove.</param>
+ [Tested]
+ public void RemoveAllCopies(T item)
+ {
+#if BAG
+ updatecheck();
+ removeIterative(ref item, true);
+#else
+
+ Remove(item);
+#endif
+ }
+
+
+ #endregion
+
+ #region IIndexed<T> Members
+
+ private Node findNode(int i)
+ {
+#if NCP
+ if (isSnapShot)
+ throw new NotSupportedException("Indexing not supported for snapshots");
+#endif
+#if MAINTAIN_SIZE
+ Node next = root;
+
+ if (i >= 0 && i < size)
+ while (true)
+ {
+ int j = next.left == null ? 0 : next.left.size;
+
+ if (i > j)
+ {
+#if BAG
+ i -= j + next.items;
+ if (i<0)
+ return next;
+#else
+ i -= j + 1;
+#endif
+ next = next.right;
+ }
+ else if (i == j)
+ return next;
+ else
+ next = next.left;
+ }
+
+ throw new IndexOutOfRangeException();
+#else
+ throw new NotSupportedException();
+#endif
+ }
+
+
+ /// <summary>
+ /// <exception cref="IndexOutOfRangeException"/> if i is negative or
+ /// >= the size of the collection.
+ /// </summary>
+ /// <value>The i'th item of this list.</value>
+ /// <param name="i">the index to lookup</param>
+ [Tested]
+ public T this[int i] { [Tested] get { return findNode(i).item; } }
+
+
+ /// <summary>
+ /// Searches for an item in the list going forwrds from the start.
+ /// </summary>
+ /// <param name="item">Item to search for.</param>
+ /// <returns>Index of item from start.</returns>
+ [Tested]
+ public int IndexOf(T item)
+ {
+ int upper;
+
+ return indexOf(item, out upper);
+ }
+
+
+ private int indexOf(T item, out int upper)
+ {
+#if NCP
+ if (isSnapShot)
+ throw new NotSupportedException("Indexing not supported for snapshots");
+#endif
+#if MAINTAIN_SIZE
+ int ind = 0; Node next = root;
+
+ while (next != null)
+ {
+ int comp = comparer.Compare(item, next.item);
+
+ if (comp < 0)
+ next = next.left;
+ else
+ {
+ int leftcnt = next.left == null ? 0 : next.left.size;
+
+ if (comp == 0)
+ {
+#if BAG
+ upper = ind + leftcnt + next.items - 1;
+ return ind + leftcnt;
+#else
+ return upper = ind + leftcnt;
+#endif
+ }
+ else
+ {
+#if BAG
+ ind = ind + next.items + leftcnt;
+#else
+ ind = ind + 1 + leftcnt;
+#endif
+ next = next.right;
+ }
+ }
+ }
+#endif
+ upper = -1;
+ return -1;
+ }
+
+
+ /// <summary>
+ /// Searches for an item in the list going backwords from the end.
+ /// </summary>
+ /// <param name="item">Item to search for.</param>
+ /// <returns>Index of of item from the end.</returns>
+ [Tested]
+ public int LastIndexOf(T item)
+ {
+#if BAG
+ int res;
+ indexOf(item, out res);
+ return res;
+#else
+ //We have NoDuplicates==true for the set
+ return IndexOf(item);
+#endif
+ }
+
+
+ /// <summary>
+ /// Remove the item at a specific position of the list.
+ /// <exception cref="IndexOutOfRangeException"/> if i is negative or
+ /// >= the size of the collection.
+ /// </summary>
+ /// <param name="i">The index of the item to remove.</param>
+ /// <returns>The removed item.</returns>
+ [Tested]
+ public T RemoveAt(int i)
+ {
+ updatecheck();
+#if MAINTAIN_SIZE
+ if (i < 0 || i >= size)
+ throw new IndexOutOfRangeException("Index out of range for sequenced collection");
+
+ //We must follow the pattern of removeIterative()
+ while (dirs.Length < 2 * blackdepth)
+ {
+ dirs = new int[2 * dirs.Length];
+ path = new Node[2 * dirs.Length];
+ }
+
+ int level = 0;
+ Node cursor = root;
+
+ while (true)
+ {
+ int j = cursor.left == null ? 0 : cursor.left.size;
+
+ if (i > j)
+ {
+#if BAG
+ i -= j + cursor.items;
+ if (i<0)
+ break;
+#else
+ i -= j + 1;
+#endif
+ dirs[level] = -1;
+ path[level++] = cursor;
+ cursor = cursor.right;
+ }
+ else if (i == j)
+ break;
+ else
+ {
+ dirs[level] = 1;
+ path[level++] = cursor;
+ cursor = cursor.left;
+ }
+ }
+
+ T retval = cursor.item;
+
+#if BAG
+ if (cursor.items>1)
+ {
+ resplicebag(level, cursor);
+ size--;
+ return retval;
+ }
+#endif
+ removeIterativePhase2(cursor, level);
+ return retval;
+#else
+ throw new NotSupportedException();
+#endif
+ }
+
+#if BAG
+ private void resplicebag(int level, Node cursor)
+ {
+#if NCP
+ Node.CopyNode(ref cursor, maxsnapid, generation);
+#endif
+ cursor.items--;
+ cursor.size--;
+ while (level-- > 0)
+ {
+ Node kid = cursor;
+
+ cursor = path[level];
+#if NCP
+ Node.update(ref cursor, dirs[level] > 0, kid, maxsnapid, generation);
+#endif
+ cursor.size--;
+ path[level] = null;
+ }
+ }
+#endif
+ /// <summary>
+ /// Remove all items in an index interval.
+ /// <exception cref="IndexOutOfRangeException"/>???.
+ /// </summary>
+ /// <param name="start">The index of the first item to remove.</param>
+ /// <param name="count">The number of items to remove.</param>
+ [Tested]
+ public void RemoveInterval(int start, int count)
+ {
+ if (start < 0 || count < 0)
+ throw new ArgumentOutOfRangeException();
+
+ if (start + count > this.size)
+ throw new ArgumentException();
+
+ updatecheck();
+
+ //This is terrible for large count. We should split the tree at
+ //the endpoints of the range and fuse the parts!
+ //We really need good internal destructive split and catenate functions!
+ for (int i = 0; i < count; i++)
+ RemoveAt(start);
+ }
+
+
+ /// <summary>
+ /// <exception cref="IndexOutOfRangeException"/>.
+ /// </summary>
+ /// <value>The directed collection of items in a specific index interval.</value>
+ /// <param name="start">The low index of the interval (inclusive).</param>
+ /// <param name="end">The high index of the interval (exclusive).</param>
+ [Tested]
+ public IDirectedCollectionValue<T> this[int start, int end]
+ {
+ [Tested]
+ get
+ {
+ checkRange(start, end - start);
+ return new Interval(this, start, end - start, true);
+ }
+ }
+
+ #region Interval nested class
+ class Interval: CollectionValueBase<T>, IDirectedCollectionValue<T>
+ {
+ int start, length, stamp;
+
+ bool forwards;
+
+ TreeBag<T> tree;
+
+
+ internal Interval(TreeBag<T> tree, int start, int count, bool forwards)
+ {
+#if NCP
+ if (tree.isSnapShot)
+ throw new NotSupportedException("Indexing not supported for snapshots");
+#endif
+ this.start = start; this.length = count;this.forwards = forwards;
+ this.tree = tree; this.stamp = tree.stamp;
+ }
+
+
+ [Tested]
+ public override int Count { [Tested]get { return length; } }
+
+
+ public override Speed CountSpeed { get { return Speed.Constant; } }
+
+ [Tested]
+ public override MSG.IEnumerator<T> GetEnumerator()
+ {
+#if MAINTAIN_SIZE
+ tree.modifycheck(stamp);
+#if BAG
+ int togo;
+#endif
+ Node cursor = tree.root;
+ Node[] path = new Node[2 * tree.blackdepth];
+ int level = 0, totaltogo = length;
+
+ if (totaltogo == 0)
+ yield break;
+
+ if (forwards)
+ {
+ int i = start;
+
+ while (true)
+ {
+ int j = cursor.left == null ? 0 : cursor.left.size;
+
+ if (i > j)
+ {
+#if BAG
+ i -= j + cursor.items;
+ if (i < 0)
+ {
+ togo = cursor.items + i;
+ break;
+ }
+#else
+ i -= j + 1;
+#endif
+ cursor = cursor.right;
+ }
+ else if (i == j)
+ {
+#if BAG
+ togo = cursor.items;
+#endif
+ break;
+ }
+ else
+ {
+ path[level++] = cursor;
+ cursor = cursor.left;
+ }
+ }
+
+ T current = cursor.item;
+
+ while (totaltogo-- > 0)
+ {
+ yield return current;
+ tree.modifycheck(stamp);
+#if BAG
+ if (--togo > 0)
+ continue;
+#endif
+ if (cursor.right != null)
+ {
+ path[level] = cursor = cursor.right;
+ while (cursor.left != null)
+ path[++level] = cursor = cursor.left;
+ }
+ else if (level == 0)
+ yield break;
+ else
+ cursor = path[--level];
+
+ current = cursor.item;
+#if BAG
+ togo = cursor.items;
+#endif
+ }
+ }
+ else
+ {
+ int i = start + length - 1;
+
+ while (true)
+ {
+ int j = cursor.left == null ? 0 : cursor.left.size;
+
+ if (i > j)
+ {
+#if BAG
+ if (i - j < cursor.items)
+ {
+ togo = i - j + 1;
+ break;
+ }
+ i -= j + cursor.items;
+#else
+ i -= j + 1;
+#endif
+ path[level++] = cursor;
+ cursor = cursor.right;
+ }
+ else if (i == j)
+ {
+#if BAG
+ togo = 1;
+#endif
+ break;
+ }
+ else
+ {
+ cursor = cursor.left;
+ }
+ }
+
+ T current = cursor.item;
+
+ while (totaltogo-- > 0)
+ {
+ yield return current;
+ tree.modifycheck(stamp);
+#if BAG
+ if (--togo > 0)
+ continue;
+#endif
+ if (cursor.left != null)
+ {
+ path[level] = cursor = cursor.left;
+ while (cursor.right != null)
+ path[++level] = cursor = cursor.right;
+ }
+ else if (level == 0)
+ yield break;
+ else
+ cursor = path[--level];
+
+ current = cursor.item;
+#if BAG
+ togo = cursor.items;
+#endif
+ }
+ }
+
+#else
+ throw new NotSupportedException();
+#endif
+ }
+
+
+ [Tested]
+ public IDirectedCollectionValue<T> Backwards()
+ { return new Interval(tree, start, length, !forwards); }
+
+
+ [Tested]
+ IDirectedEnumerable<T> C5.IDirectedEnumerable<T>.Backwards()
+ { return Backwards(); }
+
+
+ [Tested]
+ public EnumerationDirection Direction
+ {
+ [Tested]
+ get
+ {
+ return forwards ? EnumerationDirection.Forwards : EnumerationDirection.Backwards;
+ }
+ }
+ }
+ #endregion
+
+ /// <summary>
+ /// Create a collection containing the same items as this collection, but
+ /// whose enumerator will enumerate the items backwards. The new collection
+ /// will become invalid if the original is modified. Method typicaly used as in
+ /// <code>foreach (T x in coll.Backwards()) {...}</code>
+ /// </summary>
+ /// <returns>The backwards collection.</returns>
+ [Tested]
+ public IDirectedCollectionValue<T> Backwards() { return RangeAll().Backwards(); }
+
+
+ [Tested]
+ IDirectedEnumerable<T> IDirectedEnumerable<T>.Backwards() { return Backwards(); }
+
+ #endregion
+
+ #region ISequenced Members
+ [Tested]
+ int ISequenced<T>.GetHashCode() { return sequencedhashcode(); }
+
+
+ [Tested]
+ bool ISequenced<T>.Equals(ISequenced<T> that) { return sequencedequals(that); }
+ #endregion
+
+ #region PriorityQueue Members
+
+ /// <summary>
+ /// The comparer object supplied at creation time for this collection
+ /// </summary>
+ /// <value>The comparer</value>
+ public IComparer<T> Comparer { get { return comparer; } }
+
+
+ /// <summary>
+ /// Find the current least item of this priority queue.
+ /// </summary>
+ /// <returns>The least item.</returns>
+ [Tested]
+ public T FindMin()
+ {
+ if (size == 0)
+ throw new InvalidOperationException("Priority queue is empty");
+#if MAINTAIN_EXTREMA
+ return min;
+#else
+ Node cursor = root, next = left(cursor);
+
+ while (next != null)
+ {
+ cursor = next;
+ next = left(cursor);
+ }
+
+ return cursor.item;
+#endif
+ }
+
+
+ /// <summary>
+ /// Remove the least item from this priority queue.
+ /// </summary>
+ /// <returns>The removed item.</returns>
+ [Tested]
+ public T DeleteMin()
+ {
+ updatecheck();
+
+ //persistence guard?
+ if (size == 0)
+ throw new InvalidOperationException("Priority queue is empty");
+
+ //We must follow the pattern of removeIterative()
+ stackcheck();
+
+ int level = 0;
+ Node cursor = root;
+
+ while (cursor.left != null)
+ {
+ dirs[level] = 1;
+ path[level++] = cursor;
+ cursor = cursor.left;
+ }
+
+ T retval = cursor.item;
+
+#if BAG
+ if (cursor.items > 1)
+ {
+ resplicebag(level, cursor);
+ size--;
+ return retval;
+ }
+#endif
+ removeIterativePhase2(cursor, level);
+ return retval;
+ }
+
+
+ /// <summary>
+ /// Find the current largest item of this priority queue.
+ /// </summary>
+ /// <returns>The largest item.</returns>
+ [Tested]
+ public T FindMax()
+ {
+ if (size == 0)
+ throw new InvalidOperationException("Priority queue is empty");
+
+#if MAINTAIN_EXTREMA
+ return max;
+#else
+ Node cursor = root, next = right(cursor);
+
+ while (next != null)
+ {
+ cursor = next;
+ next = right(cursor);
+ }
+
+ return cursor.item;
+#endif
+ }
+
+
+ /// <summary>
+ /// Remove the largest item from this priority queue.
+ /// </summary>
+ /// <returns>The removed item.</returns>
+ [Tested]
+ public T DeleteMax()
+ {
+ //persistence guard?
+ updatecheck();
+ if (size == 0)
+ throw new InvalidOperationException("Priority queue is empty");
+
+ //We must follow the pattern of removeIterative()
+ stackcheck();
+
+ int level = 0;
+ Node cursor = root;
+
+ while (cursor.right != null)
+ {
+ dirs[level] = -1;
+ path[level++] = cursor;
+ cursor = cursor.right;
+ }
+
+ T retval = cursor.item;
+
+#if BAG
+ if (cursor.items > 1)
+ {
+ resplicebag(level, cursor);
+ size--;
+ return retval;
+ }
+#endif
+ removeIterativePhase2(cursor, level);
+ return retval;
+ }
+ #endregion
+
+ #region IPredecesorStructure<T> Members
+
+ /// <summary>
+ /// Find the strict predecessor in the sorted collection of a particular value,
+ /// i.e. the largest item in the collection less than the supplied value.
+ /// <exception cref="InvalidOperationException"/> if no such element exists (the
+ /// supplied value is less than or equal to the minimum of this collection.)
+ /// </summary>
+ /// <param name="item">The item to find the predecessor for.</param>
+ /// <returns>The predecessor.</returns>
+ [Tested]
+ public T Predecessor(T item)
+ {
+ Node cursor = root, bestsofar = null;
+
+ while (cursor != null)
+ {
+ int comp = comparer.Compare(cursor.item, item);
+
+ if (comp < 0)
+ {
+ bestsofar = cursor;
+ cursor = right(cursor);
+ }
+ else if (comp == 0)
+ {
+ cursor = left(cursor);
+ while (cursor != null)
+ {
+ bestsofar = cursor;
+ cursor = right(cursor);
+ }
+ }
+ else
+ cursor = left(cursor);
+ }
+
+ if (bestsofar != null)
+ return bestsofar.item;
+ else
+ throw new ArgumentOutOfRangeException("item", item, "Below minimum of set");
+ }
+
+
+ /// <summary>
+ /// Find the weak predecessor in the sorted collection of a particular value,
+ /// i.e. the largest item in the collection less than or equal to the supplied value.
+ /// <exception cref="InvalidOperationException"/> if no such element exists (the
+ /// supplied value is less than the minimum of this collection.)
+ /// </summary>
+ /// <param name="item">The item to find the weak predecessor for.</param>
+ /// <returns>The weak predecessor.</returns>
+ [Tested]
+ public T WeakPredecessor(T item)
+ {
+ Node cursor = root, bestsofar = null;
+
+ while (cursor != null)
+ {
+ int comp = comparer.Compare(cursor.item, item);
+
+ if (comp < 0)
+ {
+ bestsofar = cursor;
+ cursor = right(cursor);
+ }
+ else if (comp == 0)
+ return cursor.item;
+ else
+ cursor = left(cursor);
+ }
+
+ if (bestsofar != null)
+ return bestsofar.item;
+ else
+ throw new ArgumentOutOfRangeException("item", item, "Below minimum of set");
+ }
+
+
+ /// <summary>
+ /// Find the strict successor in the sorted collection of a particular value,
+ /// i.e. the least item in the collection greater than the supplied value.
+ /// <exception cref="InvalidOperationException"/> if no such element exists (the
+ /// supplied value is greater than or equal to the maximum of this collection.)
+ /// </summary>
+ /// <param name="item">The item to find the successor for.</param>
+ /// <returns>The successor.</returns>
+ [Tested]
+ public T Successor(T item)
+ {
+ Node cursor = root, bestsofar = null;
+
+ while (cursor != null)
+ {
+ int comp = comparer.Compare(cursor.item, item);
+
+ if (comp > 0)
+ {
+ bestsofar = cursor;
+ cursor = left(cursor);
+ }
+ else if (comp == 0)
+ {
+ cursor = right(cursor);
+ while (cursor != null)
+ {
+ bestsofar = cursor;
+ cursor = left(cursor);
+ }
+ }
+ else
+ cursor = right(cursor);
+ }
+
+ if (bestsofar != null)
+ return bestsofar.item;
+ else
+ throw new ArgumentOutOfRangeException("item", item, "Above maximum of set");
+ }
+
+
+ /// <summary>
+ /// Find the weak successor in the sorted collection of a particular value,
+ /// i.e. the least item in the collection greater than or equal to the supplied value.
+ /// <exception cref="InvalidOperationException"/> if no such element exists (the
+ /// supplied value is greater than the maximum of this collection.)
+ /// </summary>
+ /// <param name="item">The item to find the weak successor for.</param>
+ /// <returns>The weak successor.</returns>
+ [Tested]
+ public T WeakSuccessor(T item)
+ {
+ Node cursor = root, bestsofar = null;
+
+ while (cursor != null)
+ {
+ int comp = comparer.Compare(cursor.item, item);
+
+ if (comp == 0)
+ return cursor.item;
+ else if (comp > 0)
+ {
+ bestsofar = cursor;
+ cursor = left(cursor);
+ }
+ else
+ cursor = right(cursor);
+ }
+
+ if (bestsofar != null)
+ return bestsofar.item;
+ else
+ throw new ArgumentOutOfRangeException("item", item, "Above maximum of set");
+ }
+
+ #endregion
+
+ #region ISorted<T> Members
+
+ /// <summary>
+ /// Query this sorted collection for items greater than or equal to a supplied value.
+ /// </summary>
+ /// <param name="bot">The lower bound (inclusive).</param>
+ /// <returns>The result directed collection.</returns>
+ [Tested]
+ public IDirectedCollectionValue<T> RangeFrom(T bot)
+ { return new Range(this, true, bot, false, default(T), EnumerationDirection.Forwards); }
+
+
+ /// <summary>
+ /// Query this sorted collection for items between two supplied values.
+ /// </summary>
+ /// <param name="bot">The lower bound (inclusive).</param>
+ /// <param name="top">The upper bound (exclusive).</param>
+ /// <returns>The result directed collection.</returns>
+ [Tested]
+ public IDirectedCollectionValue<T> RangeFromTo(T bot, T top)
+ { return new Range(this, true, bot, true, top, EnumerationDirection.Forwards); }
+
+
+ /// <summary>
+ /// Query this sorted collection for items less than a supplied value.
+ /// </summary>
+ /// <param name="top">The upper bound (exclusive).</param>
+ /// <returns>The result directed collection.</returns>
+ [Tested]
+ public IDirectedCollectionValue<T> RangeTo(T top)
+ { return new Range(this, false, default(T), true, top, EnumerationDirection.Forwards); }
+
+
+ /// <summary>
+ /// Create a directed collection with the same items as this collection.
+ /// </summary>
+ /// <returns>The result directed collection.</returns>
+ [Tested]
+ public IDirectedCollectionValue<T> RangeAll()
+ { return new Range(this, false, default(T), false, default(T), EnumerationDirection.Forwards); }
+
+
+ [Tested]
+ IDirectedEnumerable<T> ISorted<T>.RangeFrom(T bot) { return RangeFrom(bot); }
+
+
+ [Tested]
+ IDirectedEnumerable<T> ISorted<T>.RangeFromTo(T bot, T top) { return RangeFromTo(bot, top); }
+
+
+ [Tested]
+ IDirectedEnumerable<T> ISorted<T>.RangeTo(T top) { return RangeTo(top); }
+
+
+ //Utility for CountXxxx. Actually always called with strict = true.
+ private int countTo(T item, bool strict)
+ {
+#if NCP
+ if (isSnapShot)
+ throw new NotSupportedException("Indexing not supported for snapshots");
+#endif
+#if MAINTAIN_SIZE
+ int ind = 0, comp = 0; Node next = root;
+
+ while (next != null)
+ {
+ comp = comparer.Compare(item, next.item);
+ if (comp < 0)
+ next = next.left;
+ else
+ {
+ int leftcnt = next.left == null ? 0 : next.left.size;
+#if BAG
+ if (comp == 0)
+ return strict ? ind + leftcnt : ind + leftcnt + next.items;
+ else
+ {
+ ind = ind + next.items + leftcnt;
+ next = next.right;
+ }
+#else
+ if (comp == 0)
+ return strict ? ind + leftcnt : ind + leftcnt + 1;
+ else
+ {
+ ind = ind + 1 + leftcnt;
+ next = next.right;
+ }
+#endif
+ }
+ }
+
+ //if we get here, we are at the same side of the whole collection:
+ return ind;
+#else
+ throw new NotSupportedException("Code compiled w/o size!");
+#endif
+ }
+
+
+ /// <summary>
+ /// Perform a search in the sorted collection for the ranges in which a
+ /// non-decreasing function from the item type to <code>int</code> is
+ /// negative, zero respectively positive. If the supplied cut function is
+ /// not non-decreasing, the result of this call is undefined.
+ /// </summary>
+ /// <param name="c">The cut function <code>T</code> to <code>int</code>, given
+ /// as an <code>IComparable<T></code> object, where the cut function is
+ /// the <code>c.CompareTo(T that)</code> method.</param>
+ /// <param name="low">Returns the largest item in the collection, where the
+ /// cut function is negative (if any).</param>
+ /// <param name="lowIsValid">True if the cut function is negative somewhere
+ /// on this collection.</param>
+ /// <param name="high">Returns the least item in the collection, where the
+ /// cut function is positive (if any).</param>
+ /// <param name="highIsValid">True if the cut function is positive somewhere
+ /// on this collection.</param>
+ /// <returns></returns>
+ [Tested]
+ public bool Cut(IComparable<T> c, out T low, out bool lowIsValid, out T high, out bool highIsValid)
+ {
+ Node cursor = root, lbest = null, rbest = null;
+ bool res = false;
+
+ while (cursor != null)
+ {
+ int comp = c.CompareTo(cursor.item);
+
+ if (comp > 0)
+ {
+ lbest = cursor;
+ cursor = right(cursor);
+ }
+ else if (comp < 0)
+ {
+ rbest = cursor;
+ cursor = left(cursor);
+ }
+ else
+ {
+ res = true;
+
+ Node tmp = left(cursor);
+
+ while (tmp != null && c.CompareTo(tmp.item) == 0)
+ tmp = left(tmp);
+
+ if (tmp != null)
+ {
+ lbest = tmp;
+ tmp = right(tmp);
+ while (tmp != null)
+ {
+ if (c.CompareTo(tmp.item) > 0)
+ {
+ lbest = tmp;
+ tmp = right(tmp);
+ }
+ else
+ tmp = left(tmp);
+ }
+ }
+
+ tmp = right(cursor);
+ while (tmp != null && c.CompareTo(tmp.item) == 0)
+ tmp = right(tmp);
+
+ if (tmp != null)
+ {
+ rbest = tmp;
+ tmp = left(tmp);
+ while (tmp != null)
+ {
+ if (c.CompareTo(tmp.item) < 0)
+ {
+ rbest = tmp;
+ tmp = left(tmp);
+ }
+ else
+ tmp = right(tmp);
+ }
+ }
+
+ break;
+ }
+ }
+
+ if (highIsValid = (rbest != null))
+ high = rbest.item;
+ else
+ high = default(T);
+
+ if (lowIsValid = (lbest != null))
+ low = lbest.item;
+ else
+ low = default(T);
+
+ return res;
+ }
+
+
+ /// <summary>
+ /// Determine the number of items at or above a supplied threshold.
+ /// </summary>
+ /// <param name="bot">The lower bound (inclusive)</param>
+ /// <returns>The number of matcing items.</returns>
+ [Tested]
+ public int CountFrom(T bot) { return size - countTo(bot, true); }
+
+
+ /// <summary>
+ /// Determine the number of items between two supplied thresholds.
+ /// </summary>
+ /// <param name="bot">The lower bound (inclusive)</param>
+ /// <param name="top">The upper bound (exclusive)</param>
+ /// <returns>The number of matcing items.</returns>
+ [Tested]
+ public int CountFromTo(T bot, T top)
+ {
+ if (comparer.Compare(bot, top) >= 0)
+ return 0;
+
+ return countTo(top, true) - countTo(bot, true);
+ }
+
+
+ /// <summary>
+ /// Determine the number of items below a supplied threshold.
+ /// </summary>
+ /// <param name="top">The upper bound (exclusive)</param>
+ /// <returns>The number of matcing items.</returns>
+ [Tested]
+ public int CountTo(T top) { return countTo(top, true); }
+
+
+ /// <summary>
+ /// Remove all items of this collection above or at a supplied threshold.
+ /// </summary>
+ /// <param name="low">The lower threshold (inclusive).</param>
+ [Tested]
+ public void RemoveRangeFrom(T low)
+ {
+ updatecheck();
+
+ int count = CountFrom(low);
+
+ if (count == 0)
+ return;
+
+ for (int i = 0; i < count; i++)
+ DeleteMax();
+ }
+
+
+ /// <summary>
+ /// Remove all items of this collection between two supplied thresholds.
+ /// </summary>
+ /// <param name="low">The lower threshold (inclusive).</param>
+ /// <param name="hi">The upper threshold (exclusive).</param>
+ [Tested]
+ public void RemoveRangeFromTo(T low, T hi)
+ {
+ updatecheck();
+
+ int count = CountFromTo(low, hi);
+
+ if (count == 0)
+ return;
+
+ for (int i = 0; i < count; i++)
+ Remove(Predecessor(hi));
+ }
+
+
+ /// <summary>
+ /// Remove all items of this collection below a supplied threshold.
+ /// </summary>
+ /// <param name="hi">The upper threshold (exclusive).</param>
+ [Tested]
+ public void RemoveRangeTo(T hi)
+ {
+ updatecheck();
+
+ int count = CountTo(hi);
+
+ if (count == 0)
+ return;
+
+ for (int i = 0; i < count; i++)
+ DeleteMin();
+ }
+
+ #endregion
+
+ #region IPersistent<T> Members
+
+ private bool disposed;
+
+
+
+ /// <summary>
+ /// If this tree is a snapshot, remove registration in base tree
+ /// </summary>
+ [Tested]
+ public void Dispose()
+ {
+ Dispose(true);
+ GC.SuppressFinalize(this);
+ }
+
+
+ private void Dispose(bool disposing)
+ {
+ if (!disposed)
+ {
+ if (disposing) { }
+#if NCP
+ if (isSnapShot)
+ {
+ snapdata.Remove(generation, disposing);
+ snapdata = null;
+ root = null;
+ dirs = null;
+ path = null;
+ comparer = null;
+ disposed = true;
+ }
+ else { }
+#endif
+ }
+ }
+
+
+ /// <summary>
+ /// If this tree is a snapshot, remove registration in base tree
+ /// </summary>
+ ~TreeBag()
+ {
+ Dispose(false);
+ }
+
+
+ /// <summary>
+ /// Make a (read-only) snap shot of this collection.
+ /// </summary>
+ /// <returns>The snap shot.</returns>
+ [Tested]
+ public ISorted<T> Snapshot()
+ {
+#if NCP
+ if (isSnapShot)
+ throw new InvalidOperationException("Cannot snapshot a snapshot");
+
+ if (snapdata == null)
+ {
+ snapdata = new SnapData(this);
+ }
+
+ snapdata.Add(generation, this);
+
+ TreeBag<T> res = (TreeBag<T>)MemberwiseClone();
+
+ res.isReadOnly = true; res.isSnapShot = true;
+ maxsnapid = generation++;
+ return res;
+#endif
+ }
+
+ #endregion
+
+ #region Snapdata nested class
+ //In a class by itself: the tree itself and snapshots must have a ref to
+ //the snapids, but we do not want snapshots to have a (strong) ref to the full
+ //updatable tree, which should be garbagecollectable even if there are still
+ //live snapshots!
+ //
+ //Access to SnapData should be thread safe since we expect finalisers
+ //of snapshots to remove a snapid that is garbagecollected without
+ //having been explicitly Disposed. Therefore we access SnapData through
+ //synchronized method/properties.
+
+#if NCP
+ class SnapData
+ {
+ TreeBag<int> snapids = new TreeBag<int>(new IC());
+
+ WeakReference master;
+
+
+ internal SnapData(TreeBag<T> tree)
+ {
+ master = new WeakReference(tree);
+ }
+
+
+ [Tested]
+ public bool Add(int i, TreeBag<T> tree)
+ {
+ lock (this)
+ {
+ bool res = snapids.Add(i);
+
+ //assert the following will be i:
+ tree.maxsnapid = snapids.Count > 0 ? snapids.FindMax() : -1;
+ return res;
+ }
+ }
+
+
+ [Tested]
+ public bool Remove(int i, bool updmaxsnapid)
+ {
+ lock (this)
+ {
+ bool res = snapids.Remove(i);
+
+ if (updmaxsnapid)
+ {
+ //Is this safe or/and overkill?
+ object t = master.Target;
+
+ if (t != null && master.IsAlive)
+ {
+ ((TreeBag<T>)t).maxsnapid = snapids.Count > 0 ? snapids.FindMax() : -1;
+ }
+ }
+
+ return res;
+ }
+ }
+ }
+
+#endif
+ #endregion
+
+ #region TreeBag.Range nested class
+
+ internal class Range: CollectionValueBase<T>, IDirectedCollectionValue<T>
+ {
+ //We actually need exclusive upper and lower bounds, and flags to
+ //indicate whether the bound is present (we canot rely on default(T))
+ private int stamp;
+
+ private TreeBag<T> basis;
+
+ private T lowend, highend;
+
+ private bool haslowend, hashighend;
+
+ EnumerationDirection direction;
+
+
+ [Tested]
+ public Range(TreeBag<T> basis, bool haslowend, T lowend, bool hashighend, T highend, EnumerationDirection direction)
+ {
+ this.basis = basis;
+ stamp = basis.stamp;
+
+ //lowind will be const; should we cache highind?
+ this.lowend = lowend; //Inclusive
+ this.highend = highend;//Exclusive
+ this.haslowend = haslowend;
+ this.hashighend = hashighend;
+ this.direction = direction;
+ }
+ #region IEnumerable<T> Members
+
+
+ #region TreeBag.Range.Enumerator nested class
+
+ public class Enumerator: MSG.IEnumerator<T>
+ {
+ #region Private Fields
+ private bool valid = false, ready = true;
+
+ private IComparer<T> comparer;
+
+ private T current;
+#if BAG
+ int togo;
+#endif
+
+ private Node cursor;
+
+ private Node[] path; // stack of nodes
+
+ private int level = 0;
+
+ private Range range;
+
+ private bool forwards;
+
+ #endregion
+ [Tested]
+ public Enumerator(Range range)
+ {
+ comparer = range.basis.comparer;
+ path = new Node[2 * range.basis.blackdepth];
+ this.range = range;
+ forwards = range.direction == EnumerationDirection.Forwards;
+ cursor = new Node();
+ if (forwards)
+ cursor.right = range.basis.root;
+ else
+ cursor.left = range.basis.root;
+ range.basis.modifycheck(range.stamp);
+ }
+
+
+ int compare(T i1, T i2) { return comparer.Compare(i1, i2); }
+
+
+ /// <summary>
+ /// Undefined if enumerator is not valid (MoveNext hash been called returning true)
+ /// </summary>
+ /// <value>The current value of the enumerator.</value>
+ [Tested]
+ public T Current
+ {
+ [Tested]
+ get
+ {
+ if (valid)
+ return current;
+ else
+ throw new InvalidOperationException();
+ }
+ }
+
+
+ //Maintain a stack of nodes that are roots of
+ //subtrees not completely exported yet. Invariant:
+ //The stack nodes together with their right subtrees
+ //consists of exactly the items we have not passed
+ //yet (the top of the stack holds current item).
+ /// <summary>
+ /// Move enumerator to next item in tree, or the first item if
+ /// this is the first call to MoveNext.
+ /// <exception cref="InvalidOperationException"/> if underlying tree was modified.
+ /// </summary>
+ /// <returns>True if enumerator is valid now</returns>
+ [Tested]
+ public bool MoveNext()
+ {
+ range.basis.modifycheck(range.stamp);
+ if (!ready)
+ return false;
+#if BAG
+ if (--togo> 0)
+ return true;
+#endif
+ if (forwards)
+ {
+ if (!valid && range.haslowend)
+ {
+ cursor = cursor.right;
+ while (cursor != null)
+ {
+ int comp = compare(cursor.item, range.lowend);
+
+ if (comp > 0)
+ {
+ path[level++] = cursor;
+#if NCP
+ cursor = range.basis.left(cursor);
+#else
+ cursor = cursor.left;
+#endif
+ }
+ else if (comp < 0)
+ {
+#if NCP
+ cursor = range.basis.right(cursor);
+#else
+ cursor = cursor.right;
+#endif
+ }
+ else
+ {
+ path[level] = cursor;
+ break;
+ }
+ }
+
+ if (cursor == null)
+ {
+ if (level == 0)
+ return valid = ready = false;
+ else
+ cursor = path[--level];
+ }
+ }
+#if NCP
+ else if (range.basis.right(cursor) != null)
+ {
+ path[level] = cursor = range.basis.right(cursor);
+
+ Node next = range.basis.left(cursor);
+
+ while (next != null)
+ {
+ path[++level] = cursor = next;
+ next = range.basis.left(cursor);
+ }
+ }
+#else
+ else if (cursor.right != null)
+ {
+ path[level] = cursor = cursor.right;
+ while (cursor.left != null)
+ path[++level] = cursor = cursor.left;
+ }
+#endif
+ else if (level == 0)
+ return valid = ready = false;
+ else
+ cursor = path[--level];
+
+ current = cursor.item;
+ if (range.hashighend && compare(current, range.highend) >= 0)
+ return valid = ready = false;
+
+#if BAG
+ togo = cursor.items;
+#endif
+ return valid = true;
+ }
+ else
+ {
+ if (!valid && range.hashighend)
+ {
+ cursor = cursor.left;
+ while (cursor != null)
+ {
+ int comp = compare(cursor.item, range.highend);
+
+ if (comp < 0)
+ {
+ path[level++] = cursor;
+#if NCP
+ cursor = range.basis.right(cursor);
+#else
+ cursor = cursor.right;
+#endif
+ }
+ else
+ {
+#if NCP
+ cursor = range.basis.left(cursor);
+#else
+ cursor = cursor.left;
+#endif
+ }
+ }
+
+ if (cursor == null)
+ {
+ if (level == 0)
+ return valid = ready = false;
+ else
+ cursor = path[--level];
+ }
+ }
+#if NCP
+ else if (range.basis.left(cursor) != null)
+ {
+ path[level] = cursor = range.basis.left(cursor);
+
+ Node next = range.basis.right(cursor);
+
+ while (next != null)
+ {
+ path[++level] = cursor = next;
+ next = range.basis.right(cursor);
+ }
+ }
+#else
+ else if (cursor.left != null)
+ {
+ path[level] = cursor = cursor.left;
+ while (cursor.right != null)
+ path[++level] = cursor = cursor.right;
+ }
+#endif
+ else if (level == 0)
+ return valid = ready = false;
+ else
+ cursor = path[--level];
+
+ current = cursor.item;
+ if (range.haslowend && compare(current, range.lowend) < 0)
+ return valid = ready = false;
+
+#if BAG
+ togo = cursor.items;
+#endif
+ return valid = true;
+ }
+ }
+
+
+ [Tested]
+ public void Dispose()
+ {
+ comparer = null;
+ current = default(T);
+ cursor = null;
+ path = null;
+ range = null;
+ }
+ }
+
+ #endregion
+
+ [Tested]
+ public override MSG.IEnumerator<T> GetEnumerator() { return new Enumerator(this); }
+
+
+ [Tested]
+ public EnumerationDirection Direction { [Tested]get { return direction; } }
+
+
+ #endregion
+
+ #region Utility
+
+ bool inside(T item)
+ {
+ return (!haslowend || basis.comparer.Compare(item, lowend) >= 0) && (!hashighend || basis.comparer.Compare(item, highend) < 0);
+ }
+
+
+ void checkstamp()
+ {
+ if (stamp < basis.stamp)
+ throw new InvalidOperationException("Base collection was modified behind my back!");
+ }
+
+
+ void syncstamp() { stamp = basis.stamp; }
+
+ #endregion
+
+ [Tested]
+ public IDirectedCollectionValue<T> Backwards()
+ {
+ Range b = (Range)MemberwiseClone();
+
+ b.direction = direction == EnumerationDirection.Forwards ? EnumerationDirection.Backwards : EnumerationDirection.Forwards;
+ return b;
+ }
+
+
+ [Tested]
+ IDirectedEnumerable<T> IDirectedEnumerable<T>.Backwards() { return Backwards(); }
+
+
+ [Tested]
+ public override int Count
+ {
+ [Tested]
+ get
+ {
+ return haslowend ? (hashighend ? basis.CountFromTo(lowend, highend) : basis.CountFrom(lowend)) : (hashighend ? basis.CountTo(highend) : basis.Count);
+ }
+ }
+
+ //TODO: check that this is correct
+ public override Speed CountSpeed { get { return Speed.Log; } }
+
+ }
+
+ #endregion
+
+ #region fixheight utility
+
+#if MAINTAIN_HEIGHT
+ public void fixheight(Node n)
+ {
+ int lh = n.left == null ? 0 : n.left.height + 1;
+ int rh = n.right == null ? 0 : n.right.height + 1;
+
+ n.height = (short)(lh > rh ? lh : rh);
+ }
+#endif
+
+ #endregion
+
+ #region Diagnostics
+ /// <summary>
+ /// Display this node on the console, and recursively its subnodes.
+ /// </summary>
+ /// <param name="n">Node to display</param>
+ /// <param name="space">Indentation</param>
+ private void minidump(Node n, string space)
+ {
+ if (n == null)
+ {
+ // System.Console.WriteLine(space + "null");
+ }
+ else
+ {
+ minidump(n.right, space + " ");
+ Console.WriteLine(String.Format("{0} {4} (rank={5}, size={1}, items={8}, h={2}, gen={3}, id={6}){7}", space + n.item,
+#if MAINTAIN_SIZE
+ n.size,
+#else
+ 0,
+#endif
+#if MAINTAIN_HEIGHT
+ n.height,
+#else
+ 0,
+#endif
+#if NCP
+ n.generation,
+#endif
+ n.red ? "RED" : "BLACK",
+#if MAINTAIN_RANK
+ n.rank,
+#else
+ 0,
+#endif
+#if TRACE_ID
+ n.id,
+#else
+ 0,
+#endif
+#if NCP
+#if SEPARATE_EXTRA
+ n.extra == null ? "" : String.Format(" [extra: lg={0}, c={1}, i={2}]", n.extra.lastgeneration, n.extra.leftnode ? "L" : "R", n.extra.oldref == null ? "()" : "" + n.extra.oldref.item),
+#else
+ n.lastgeneration == -1 ? "" : String.Format(" [extra: lg={0}, c={1}, i={2}]", n.lastgeneration, n.leftnode ? "L" : "R", n.oldref == null ? "()" : "" + n.oldref.item),
+#endif
+#else
+ "",
+#endif
+#if BAG
+ n.items
+#else
+ 1
+#endif
+ ));
+ minidump(n.left, space + " ");
+ }
+ }
+
+
+ /// <summary>
+ /// Print the tree structure to the console stdout.
+ /// </summary>
+ [Tested(via = "Sawtooth")]
+ public void dump() { dump(""); }
+
+
+ /// <summary>
+ /// Print the tree structure to the console stdout.
+ /// </summary>
+ [Tested(via = "Sawtooth")]
+ public void dump(string msg)
+ {
+ Console.WriteLine(String.Format(">>>>>>>>>>>>>>>>>>> dump {0} (count={1}, blackdepth={2}, depth={3}, gen={4})", msg, size, blackdepth,
+#if MAINTAIN_HEIGHT
+ depth
+#else
+ 0
+#endif
+ ,
+#if NCP
+ generation
+#endif
+ ));
+ minidump(root, "");
+ check("", Console.Out); Console.WriteLine("<<<<<<<<<<<<<<<<<<<");
+ }
+
+
+ /// <summary>
+ /// Display this tree on the console.
+ /// </summary>
+ /// <param name="msg">Identifying string of this call to dump</param>
+ /// <param name="err">Extra (error)message to include</param>
+ void dump(string msg, string err)
+ {
+ Console.WriteLine(String.Format(">>>>>>>>>>>>>>>>>>> dump {0} (count={1}, blackdepth={2}, depth={3}, gen={4})", msg, size, blackdepth,
+#if MAINTAIN_HEIGHT
+ depth
+#else
+ 0
+#endif
+ ,
+#if NCP
+ generation
+#endif
+ ));
+ minidump(root, ""); Console.Write(err);
+ Console.WriteLine("<<<<<<<<<<<<<<<<<<<");
+ }
+
+
+ /// <summary>
+ /// Print warning m on o if b is false.
+ /// </summary>
+ /// <param name="b">Condition that should hold</param>
+ /// <param name="n">Place (used for id display)</param>
+ /// <param name="m">Message</param>
+ /// <param name="o">Output stream</param>
+ /// <returns>b</returns>
+ bool massert(bool b, Node n, string m, System.IO.TextWriter o)
+ {
+ if (!b) o.WriteLine("*** Node (item={0}, id={1}): {2}", n.item,
+#if TRACE_ID
+ n.id
+#else
+ 0
+#endif
+ , m);
+
+ return b;
+ }
+
+
+ bool rbminicheck(Node n, bool redp, int prank, System.IO.TextWriter o, out T min, out T max, out int blackheight, int maxgen)
+ {//Red-Black invariant
+ bool res = true;
+
+ res = massert(!(n.red && redp), n, "RED parent of RED node", o) && res;
+ res = massert(n.left == null || n.right != null || n.left.red, n, "Left child black, but right child empty", o) && res;
+ res = massert(n.right == null || n.left != null || n.right.red, n, "Right child black, but left child empty", o) && res;
+#if MAINTAIN_RANK
+ res = massert(n.red == (n.rank == prank), n, "Bad color", o) && res;
+ res = massert(prank <= n.rank + 1, n, "Parentrank-rank >= 2", o) && res;
+ res = massert((n.left != null && n.right != null) || n.rank == 1, n, "Rank>1 but empty child", o) && res;
+#endif
+#if BAG
+ bool sb = n.size == (n.left == null ? 0 : n.left.size) + (n.right == null ? 0 : n.right.size) + n.items;
+
+ res = massert(sb, n, "Bad size", o) && res;
+#elif MAINTAIN_SIZE
+ bool sb = n.size == (n.left == null ? 0 : n.left.size) + (n.right == null ? 0 : n.right.size) + 1;
+
+ res = massert(sb, n, "Bad size", o) && res;
+#endif
+#if MAINTAIN_HEIGHT
+ int lh = n.left == null ? 0 : n.left.height + 1;
+ int rh = n.right == null ? 0 : n.right.height + 1;
+
+ res = massert(n.height == (lh < rh ? rh : lh), n, "Bad height", o) && res;
+#endif
+ int therank =
+#if MAINTAIN_RANK
+ n.rank;
+#else
+ 0;
+#endif
+ min = max = n.item;
+
+ T otherext;
+ int lbh = 0, rbh = 0;
+
+ if (n.left != null)
+ {
+ res = rbminicheck(n.left, n.red, therank, o, out min, out otherext, out lbh, generation) && res;
+ res = massert(comparer.Compare(n.item, otherext) > 0, n, "Value not > all left children", o) && res;
+ }
+
+ if (n.right != null)
+ {
+ res = rbminicheck(n.right, n.red, therank, o, out otherext, out max, out rbh, generation) && res;
+ res = massert(comparer.Compare(n.item, otherext) < 0, n, "Value not < all right children", o) && res;
+ }
+
+ res = massert(rbh == lbh, n, "Different blackheights of children", o) && res;
+ blackheight = n.red ? rbh : rbh + 1;
+#if MAINTAIN_RANK
+ //The rank is the number of black nodes from this one to
+ //the leaves, not counting this one, but counting 1 for the empty
+ //virtual leaf nodes.
+ res = massert(n.rank == rbh + 1, n, "rank!=blackheight " + blackheight, o) && res;
+#endif
+ return res;
+ }
+
+
+
+
+#if NCP
+
+ bool rbminisnapcheck(Node n, System.IO.TextWriter o, out int size, out T min, out T max)
+ {
+ bool res = true;
+
+ min = max = n.item;
+
+ int lsz = 0, rsz = 0;
+ T otherext;
+#if SEPARATE_EXTRA
+ Node.Extra extra = n.extra;
+ Node child = (extra != null && extra.lastgeneration >= treegen && extra.leftnode) ? extra.oldref : n.left;
+#else
+ Node child = (n.lastgeneration >= generation && n.leftnode) ? n.oldref : n.left;
+#endif
+ if (child != null)
+ {
+ res = rbminisnapcheck(child, o, out lsz, out min, out otherext) && res;
+ res = massert(comparer.Compare(n.item, otherext) > 0, n, "Value not > all left children", o) && res;
+ }
+
+#if SEPARATE_EXTRA
+ child = (extra != null && extra.lastgeneration >= treegen && !extra.leftnode) ? extra.oldref : n.right;
+#else
+ child = (n.lastgeneration >= generation && !n.leftnode) ? n.oldref : n.right;
+#endif
+ if (child != null)
+ {
+ res = rbminisnapcheck(child, o, out rsz, out otherext, out max) && res;
+ res = massert(comparer.Compare(n.item, otherext) < 0, n, "Value not < all right children", o) && res;
+ }
+#if BAG
+ size = n.items + lsz + rsz;
+#else
+ size = 1 + lsz + rsz;
+#endif
+ return res;
+ }
+#endif
+
+ /// <summary>
+ /// Checks red-black invariant. Dumps tree to console if bad
+ /// </summary>
+ /// <param name="name">Title of dump</param>
+ /// <returns>false if invariant violation</returns>
+ [Tested(via = "Sawtooth")]
+ public bool Check(string name)
+ {
+ System.Text.StringBuilder e = new System.Text.StringBuilder();
+ System.IO.TextWriter o = new System.IO.StringWriter(e);
+
+ if (!check(name, o))
+ return true;
+ else
+ {
+ dump(name, e.ToString());
+ return false;
+ }
+ }
+
+
+ /// <summary>
+ /// Checks red-black invariant. Dumps tree to console if bad
+ /// </summary>
+ /// <returns>false if invariant violation</returns>
+ [Tested]
+ public bool Check()
+ {
+ //return check("", System.IO.TextWriter.Null);
+ //Console.WriteLine("bamse");
+ return Check("-");
+ }
+
+
+ bool check(string msg, System.IO.TextWriter o)
+ {
+ if (root != null)
+ {
+ T max, min;
+ int blackheight;
+#if NCP
+ if (isSnapShot)
+ {
+ //Console.WriteLine("Im'a snapshot");
+ int thesize;
+ bool rv = rbminisnapcheck(root, o, out thesize, out min, out max);
+
+ rv = massert(size == thesize, root, "bad snapshot size", o) && rv;
+ return !rv;
+ }
+#endif
+#if MAINTAIN_RANK
+ bool res = rbminicheck(root, false, root.rank + 1, o, out min, out max, out blackheight, generation);
+
+ res = massert(root.rank == blackdepth, root, "blackdepth!=root.rank", o) && res;
+#else
+ bool res = rbminicheck(root, false, 0, o, out min, out max, out blackheight, generation);
+#endif
+ res = massert(blackheight == blackdepth, root, "bad blackh/d", o) && res;
+ res = massert(!root.red, root, "root is red", o) && res;
+#if MAINTAIN_SIZE
+ res = massert(root.size == size, root, "count!=root.size", o) && res;
+#endif
+#if MAINTAIN_HEIGHT
+ res = massert(root.height == depth, root, "depth!=root.height", o) && res;
+#endif
+ return !res;
+ }
+ else
+ return false;
+ }
+ #endregion
+ }
+}
+
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