LeetCode（47）-Reverse Bits

题目：

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?

Related problem: Reverse Integer

思路：

代码：

public class Solution {
// you need treat n as an unsigned value
public int reverseBits(int n) {
int res = 0;
for(int i = 0; i < 32; i++, n >>= 1){
res = res << 1 | (n & 1);
}
return res;
}
}