Leetcode 190. Reverse Bits（反转比特数）

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?

class Solution {
public:
    uint32_t reverseBits(uint32_t n) {
        uint32_t k = 0, num = 1;
        while(num <= 32){
            if(k == 0)
                k = n & 1;
            else
                k = (k << 1) | (n & 1);
            n >>= 1;
            num++;
        }
        return k;
        
    }
};