47 lines
686 B
JavaScript
47 lines
686 B
JavaScript
'use strict';
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var arr = [];
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var charCodeCache = [];
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module.exports = function (a, b) {
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if (a === b) {
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return 0;
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}
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var aLen = a.length;
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var bLen = b.length;
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if (aLen === 0) {
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return bLen;
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}
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if (bLen === 0) {
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return aLen;
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}
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var bCharCode;
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var ret;
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var tmp;
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var tmp2;
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var i = 0;
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var j = 0;
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while (i < aLen) {
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charCodeCache[i] = a.charCodeAt(i);
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arr[i] = ++i;
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}
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while (j < bLen) {
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bCharCode = b.charCodeAt(j);
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tmp = j++;
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ret = j;
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for (i = 0; i < aLen; i++) {
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tmp2 = bCharCode === charCodeCache[i] ? tmp : tmp + 1;
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tmp = arr[i];
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ret = arr[i] = tmp > ret ? tmp2 > ret ? ret + 1 : tmp2 : tmp2 > tmp ? tmp + 1 : tmp2;
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}
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}
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return ret;
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};
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