forked from M3-Academy/challenge-algorithms-v2.0
35 lines
1.0 KiB
JavaScript
35 lines
1.0 KiB
JavaScript
export function levenshtein(a, b) {
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if (a.length === 0)
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return b.length;
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if (b.length === 0)
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return a.length;
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const matrix = [];
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let 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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let 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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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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}
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else {
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if (i > 1 &&
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j > 1 &&
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b.charAt(i - 2) === a.charAt(j - 1) &&
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b.charAt(i - 1) === a.charAt(j - 2)) {
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matrix[i][j] = matrix[i - 2][j - 2] + 1;
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}
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else {
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matrix[i][j] = Math.min(matrix[i - 1][j - 1] + 1, Math.min(matrix[i][j - 1] + 1, matrix[i - 1][j] + 1));
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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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