190.颠倒二进制位.java

/*
 * @lc app=leetcode.cn id=190 lang=java
 *
 * [190] 颠倒二进制位
 */

// @lc code=start
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 ++ ) {
            res <<= 1;
            if ((n & 1) == 1) res += 1;
            n >>= 1;
        }
        return res;
    }
}
// @lc code=end