39 lines
907 B
JavaScript
39 lines
907 B
JavaScript
// taken from stackoverflow, it's crap i know.
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module.exports = function (a, b) {
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if (a.length === 0) return b.length;
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if (b.length === 0) return a.length;
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var matrix = [];
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// increment along the first column of each row
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var i;
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for (i = 0; i <= b.length; i++) {
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matrix[i] = [i];
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}
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// increment each column in the first row
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var j;
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for (j = 0; j <= a.length; j++) {
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matrix[0][j] = j;
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}
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// Fill in the rest of the matrix
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for (i = 1; i <= b.length; i++) {
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for (j = 1; j <= a.length; j++) {
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if (b.charAt(i - 1) == a.charAt(j - 1)) {
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matrix[i][j] = matrix[i - 1][j - 1];
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} else {
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matrix[i][j] = Math.min(
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matrix[i - 1][j - 1] + 1, // substitution
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Math.min(
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matrix[i][j - 1] + 1, // insertion
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matrix[i - 1][j] + 1) // deletion
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);
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}
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}
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}
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return matrix[b.length][a.length];
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};
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