gistfile1.txt

Editor =
  (str1, str2) ->
          
    l1 = str1.length
    l2 = str2.length
    
    return Math.max l1, l2 if Math.min(l1, l2) == 0      
    
    i = 0; j = 0; distance = []

    for i in [0...l1 + 1]
      distance[i] = []
      distance[i][0] = i

    distance[0][j] = j for j in [0...l2 + 1]
    #console.log "dist1", distance
    for i in [1...l1 + 1]
      for j in [1...l2 + 1]
        distance[i][j] = Math.min distance[i - 1][j] + 1,
          distance[i][j - 1] + 1,                         
          distance[i - 1][j - 1] + `(str1.charAt(i - 1) === str2.charAt(j - 1) ? 0 : 1)`

    #console.log "dist2", distance

    distance[l1][l2]
    
alert Editor "kitten", "sitting"