code: public static void randomPathFast(int[] result, int size) {
          //Random generator = new Random();
  
          for (int i = 0; i < size; i++) result[i] = i;
          for (int k = size - 1; k > 0; k--) {
              int w = (int)Math.floor(Math.random() * (k+1));
              int temp = result[w];
              result[w] = result[k];
              result[k] = temp;
          }
      }
docs: generates random permutation of cities