docs: private int indicesFront(int[] entries) {
      int start = 0;
      for (int i = 0; i < entries.length; i++) {
        start *= numClasses;
        start += entries[i];
      }
      int offset = SloppyMath.intPow(numClasses, windowSize - entries.length);
      start *= offset;
      return start;
    }