190. 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 as 00111001011110000010100101000000).

class Solution {public:    uint32_t reverseBits(uint32_t n) {        uint32_t ans = 0;        for(int i = 0, j = 0; i < 32; ++i, ++j){            ans += n & 1;            if(j < 31)                ans <<= 1;            n >>= 1;        }        return ans;    }};