text: "use strict";
  
  var CHARSET = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ".split("");
  
  // NB: does not validate input
  exports.encode = function encode(int) {
      if (int === 0) {
          return CHARSET[0];
      }
  
      var res = "";
      while (int > 0) {
          res = CHARSET[int % 62] + res;
          int = Math.floor(int / 62);
      }
      return res;
  };
  
  exports.decode = function decode(str) {
      var res = 0,
          length = str.length,
          i, char;
      for (i = 0; i < length; i++) {
          char = str.charCodeAt(i);
          if (char < 58) { // 0-9
              char = char - 48;
          } else if (char < 91) { // A-Z
              char = char - 29;
          } else { // a-z
              char = char - 87;
          }
          res += char * Math.pow(62, length - i - 1);
      }
      return res;
  };
  