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package org.bouncycastle.pqc.math.ntru.euclid;
/**
* Extended Euclidean Algorithm in <code>int</code>s
*/
public class IntEuclidean
{
public int x, y, gcd;
private IntEuclidean()
{
}
/**
* Runs the EEA on two <code>int</code>s<br/>
* Implemented from pseudocode on <a href="http://en.wikipedia.org/wiki/Extended_Euclidean_algorithm">Wikipedia</a>.
*
* @param a
* @param b
* @return a <code>IntEuclidean</code> object that contains the result in the variables <code>x</code>, <code>y</code>, and <code>gcd</code>
*/
public static IntEuclidean calculate(int a, int b)
{
int x = 0;
int lastx = 1;
int y = 1;
int lasty = 0;
while (b != 0)
{
int quotient = a / b;
int temp = a;
a = b;
b = temp % b;
temp = x;
x = lastx - quotient * x;
lastx = temp;
temp = y;
y = lasty - quotient * y;
lasty = temp;
}
IntEuclidean result = new IntEuclidean();
result.x = lastx;
result.y = lasty;
result.gcd = a;
return result;
}
}
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