LeetCode 190: Reverse Bits

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).

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

解题思路

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