62 lines
1.5 KiB
JavaScript
62 lines
1.5 KiB
JavaScript
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(function (exports) {
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'use strict';
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var levenshteinDistance = (function () {
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function levenshteinDistance (s, ls, t, lt) {
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var memo = [];
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var currRowMemo;
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var i;
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var k;
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for (k = 0; k <= lt; k += 1) {
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memo[k] = k;
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}
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for (i = 1; i <= ls; i += 1) {
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currRowMemo = [i];
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for (k = 1; k <= lt; k += 1) {
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currRowMemo[k] = Math.min(
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currRowMemo[k - 1] + 1,
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memo[k] + 1,
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memo[k - 1] + (s[i - 1] !== t[k - 1] ? 1 : 0)
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);
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}
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memo = currRowMemo;
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}
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return memo[lt];
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}
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/**
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* The Levenshtein distance between two strings is a minimum number
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* of edits needed to transform one string into the other, with the
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* allowable edit operations being insertion, deletion,
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* or substitution of a single character.
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*
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* @public
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* @module others/levenshtein-distance
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*
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* @example
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*
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* var dist = require('path-to-algorithms/src/others/' +
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* 'levenshtein-distance').levenshteinDistance;
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* console.log(dist('kitten', 'sitting')); // 3
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*
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* @param {String} s Source string.
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* @param {String} t Target string.
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* @return {Number} Minimum number of edits needed
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* to transform source string into the target string.
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*/
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return function (s, t) {
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return levenshteinDistance(s, s.length, t, t.length);
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};
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}());
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exports.levenshteinDistance = levenshteinDistance;
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}(typeof exports === 'undefined' ? window : exports));
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