Reverse Bits

Reverse bits of a given 32 bits unsigned integer.

For example, given input 43261596 (represented in binary as 00000010100101000001111010011100), return 964176192 (represented in binary as00111001011110000010100101000000).

Follow up:
If this function is called many times, how would you optimize it?

Analyse:

Extract the right-most bit every time, then put it at the corresponding left place in m.

Pay attention to the place of m = (m<<1)

class Solution {
public:
    uint32_t reverseBits(uint32_t n) {
        uint32_t m = 0;
        for(int i = 0; i < 32; i++){
            m = (m << 1);
            m = (n & 1) | m;
            n = (n >> 1);
        }
        return m;
    }
};