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"use strict";
const peq = new Uint32Array(0x10000);
const myers_32 = (a, b) => {
const n = a.length;
const m = b.length;
const lst = 1 << (n - 1);
let pv = -1;
let mv = 0;
let sc = n;
let i = n;
while (i--) {
peq[a.charCodeAt(i)] |= 1 << i;
}
for (i = 0; i < m; i++) {
let eq = peq[b.charCodeAt(i)];
const xv = eq | mv;
eq |= ((eq & pv) + pv) ^ pv;
mv |= ~(eq | pv);
pv &= eq;
if (mv & lst) {
sc++;
}
if (pv & lst) {
sc--;
}
mv = (mv << 1) | 1;
pv = (pv << 1) | ~(xv | mv);
mv &= xv;
}
i = n;
while (i--) {
peq[a.charCodeAt(i)] = 0;
}
return sc;
};
const myers_x = (a, b) => {
const n = a.length;
const m = b.length;
const mhc = [];
const phc = [];
const hsize = Math.ceil(n / 32);
const vsize = Math.ceil(m / 32);
let score = m;
for (let i = 0; i < hsize; i++) {
phc[i] = -1;
mhc[i] = 0;
}
let j = 0;
for (; j < vsize - 1; j++) {
let mv = 0;
let pv = -1;
const start = j * 32;
const end = Math.min(32, m) + start;
for (let k = start; k < end; k++) {
peq[b.charCodeAt(k)] |= 1 << k;
}
score = m;
for (let i = 0; i < n; i++) {
const eq = peq[a.charCodeAt(i)];
const pb = (phc[(i / 32) | 0] >>> i) & 1;
const mb = (mhc[(i / 32) | 0] >>> i) & 1;
const xv = eq | mv;
const xh = ((((eq | mb) & pv) + pv) ^ pv) | eq | mb;
let ph = mv | ~(xh | pv);
let mh = pv & xh;
if ((ph >>> 31) ^ pb) {
phc[(i / 32) | 0] ^= 1 << i;
}
if ((mh >>> 31) ^ mb) {
mhc[(i / 32) | 0] ^= 1 << i;
}
ph = (ph << 1) | pb;
mh = (mh << 1) | mb;
pv = mh | ~(xv | ph);
mv = ph & xv;
}
for (let k = start; k < end; k++) {
peq[b.charCodeAt(k)] = 0;
}
}
let mv = 0;
let pv = -1;
const start = j * 32;
const end = Math.min(32, m - start) + start;
for (let k = start; k < end; k++) {
peq[b.charCodeAt(k)] |= 1 << k;
}
score = m;
for (let i = 0; i < n; i++) {
const eq = peq[a.charCodeAt(i)];
const pb = (phc[(i / 32) | 0] >>> i) & 1;
const mb = (mhc[(i / 32) | 0] >>> i) & 1;
const xv = eq | mv;
const xh = ((((eq | mb) & pv) + pv) ^ pv) | eq | mb;
let ph = mv | ~(xh | pv);
let mh = pv & xh;
score += (ph >>> (m - 1)) & 1;
score -= (mh >>> (m - 1)) & 1;
if ((ph >>> 31) ^ pb) {
phc[(i / 32) | 0] ^= 1 << i;
}
if ((mh >>> 31) ^ mb) {
mhc[(i / 32) | 0] ^= 1 << i;
}
ph = (ph << 1) | pb;
mh = (mh << 1) | mb;
pv = mh | ~(xv | ph);
mv = ph & xv;
}
for (let k = start; k < end; k++) {
peq[b.charCodeAt(k)] = 0;
}
return score;
};
const distance = (a, b) => {
if (a.length > b.length) {
const tmp = b;
b = a;
a = tmp;
}
if (a.length === 0) {
return b.length;
}
if (a.length <= 32) {
return myers_32(a, b);
}
return myers_x(a, b);
};
const closest = (str, arr) => {
let min_distance = Infinity;
let min_index = 0;
for (let i = 0; i < arr.length; i++) {
const dist = distance(str, arr[i]);
if (dist < min_distance) {
min_distance = dist;
min_index = i;
}
}
return arr[min_index];
};
module.exports = {
closest, distance
}
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