docs: public void setBit(int index, boolean set)
      {
          assertValidIndex(index);
          int word = index / WORD_LENGTH;
          int offset = index % WORD_LENGTH;
          if (set)
          {
              data[word] |= (1 << offset);
          }
          else // Unset the bit.
          {
              data[word] &= ~(1 << offset);
          }
      }