#Leetcode# 190. Reverse Bits

https://leetcode.com/problems/reverse-bits/

Reverse bits of a given 32 bits unsigned integer.

Example:

Input: 43261596
Output: 964176192
Explanation: 43261596 represented in binary as 00000010100101000001111010011100, 
             return 964176192 represented in binary as 00111001011110000010100101000000.

代码：

class Solution {
public:
    uint32_t reverseBits(uint32_t n) {
        vector<int> ans;
        while(n) {
            ans.push_back(n % 2);
            n /= 2;
        }
        for(int i = ans.size(); i < 32; i ++)
            ans.push_back(0);
        int sum = 0;
        for(int i = 0; i <32; i ++)
            sum += ans[i] * (1 <<(31 - i));
        
        return sum;
    }
};

　　Easy 杀手