package main

func reverseBits2(num uint32) uint32 {
	num = (num << 16) | (num >> 16)
	num = ((num & 0x00ff00ff)<< 8) | ((num & 0xff00ff00) >> 8)
	num = ((num & 0x0f0f0f0f) << 4) | ((num & 0xf0f0f0f0) >> 4)
	num = ((num & 0x33333333) << 2) | ((num & 0xcccccccc) >> 2)
	num = ((num & 0x55555555) << 1) | ((num & 0xaaaaaaaa) >> 1)
	return num
}