func IterateBits(n uint) int {
	i := 0
	for n != 0 {
		// amd64/v1,amd64/v2:"BSFQ",-"CMOVEQ"
		// amd64/v3:"TZCNTQ"
		i += bits.TrailingZeros(n)
		n &= n - 1
	}
	return i
}

func IterateBits64(n uint64) int {
	i := 0
	for n != 0 {
		// amd64/v1,amd64/v2:"BSFQ",-"CMOVEQ"
		// amd64/v3:"TZCNTQ"
		i += bits.TrailingZeros64(n)
		n &= n - 1
	}
	return i
}