HappyLeetcode58:Reverse Bits

標籤：

Reverse bits of a given 32 bits unsigned integer.

For example, given input 43261596 (represented in binary as 00000010100101000001111010011100), return 964176192 (represented in binary as00111001011110000010100101000000).

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

Related problem: Reverse Integer

Credits:
Special thanks to @ts for adding this problem and creating all test cases.

這道題的難度不大，主要是位元運算。因為是無符號數，所以我可以放心的讓原資料右移，新資料得到新的一位之後進行左移。最終得到結果。對與有符號數，方法亦然。

代碼如下：

class Solution {public:    uint32_t reverseBits(uint32_t n) {        uint32_t result = 0;        int bit;        for (int i = 0; i < 32; ++i)        {            bit = n & 0x01;            n >>= 1;            result <<= 1;            result = result | bit;        }        return result;    }};

值得一提的是， >>=和<<=這兩個符號之前基本上就沒有用過，所以第一次寫代碼的時候漏掉了=號，今後注意。

HappyLeetcode58:Reverse Bits