levenshtein distance implementation in Node.js

ld.js

#!/usr/bin/env node


function levenshtein_distance(a, b) {
  var m = [];
  var i, j, x;

  for (i = 0; i <= a.length; i++) {
    m[i] = [];
  }

  for (i = 0; i <= a.length; i++) {
    m[i][0] = i;
  }

  for (j = 0; j <= b.length; j++) {
    m[0][j] = j;
  }

  for (i = 1; i <= a.length; i++) {
    for (j = 1; j <= b.length; j++) {
      if (a[i-1] == b[j-1]) {
        x = 0;
      } else {
        x = 1;
      }
      m[i][j] = Math.min(m[i-1][j] + 1, m[i][j-1] + 1, m[i-1][j-1] + x);
    }
  }

  return m[a.length][b.length];
}


var s1 = process.argv[2];
var s2 = process.argv[3];

console.log(levenshtein_distance(s1, s2));