code: public static int[] range(int start, int end) {
      int[] out = new int[end - start];
      for(int i = 0, j = start; j < end; i++, j++) {
        out[i] = j;
      }
      return out;
    }
docs: Initialize an integer value range.
  
  @param start Starting value
  @param end End value (exclusive)
  @return Array of integers start..end, excluding end.