File size: 3,668 Bytes
ffe3673 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 | 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 = (b, a) => {
const n = a.length;
const m = b.length;
const mhc = [];
const phc = [];
const hsize = Math.ceil(n / 32);
const vsize = Math.ceil(m / 32);
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 vlen = Math.min(32, m) + start;
for (let k = start; k < vlen; k++) {
peq[b.charCodeAt(k)] |= 1 << k;
}
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 < vlen; k++) {
peq[b.charCodeAt(k)] = 0;
}
}
let mv = 0;
let pv = -1;
const start = j * 32;
const vlen = Math.min(32, m - start) + start;
for (let k = start; k < vlen; k++) {
peq[b.charCodeAt(k)] |= 1 << k;
}
let 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 < vlen; 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 (b.length === 0) {
return a.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];
};
export { closest, distance };
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