const bitCount32 = (num: number): number => {
  const a = num - ((num >> 1) & 0x55555555)
  const b = (a & 0x33333333) + ((a >> 2) & 0x33333333)
  return ((b + (b >> 4) & 0xF0F0F0F) * 0x1010101) >> 24
}