forked from Fediversity/fediversity.eu
35 lines
1 KiB
JavaScript
35 lines
1 KiB
JavaScript
|
export function levenshtein(a, b) {
|
||
|
|
if (a.length === 0)
|
||
|
|
return b.length;
|
||
|
|
if (b.length === 0)
|
||
|
|
return a.length;
|
||
|
|
const matrix = [];
|
||
|
|
let i;
|
||
|
|
for (i = 0; i <= b.length; i++) {
|
||
|
|
matrix[i] = [i];
|
||
|
|
}
|
||
|
|
let j;
|
||
|
|
for (j = 0; j <= a.length; j++) {
|
||
|
|
matrix[0][j] = j;
|
||
|
|
}
|
||
|
|
for (i = 1; i <= b.length; i++) {
|
||
|
|
for (j = 1; j <= a.length; j++) {
|
||
|
|
if (b.charAt(i - 1) === a.charAt(j - 1)) {
|
||
|
|
matrix[i][j] = matrix[i - 1][j - 1];
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
if (i > 1 &&
|
||
|
|
j > 1 &&
|
||
|
|
b.charAt(i - 2) === a.charAt(j - 1) &&
|
||
|
|
b.charAt(i - 1) === a.charAt(j - 2)) {
|
||
|
|
matrix[i][j] = matrix[i - 2][j - 2] + 1;
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
matrix[i][j] = Math.min(matrix[i - 1][j - 1] + 1, Math.min(matrix[i][j - 1] + 1, matrix[i - 1][j] + 1));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return matrix[b.length][a.length];
|
||
|
|
}
|