LeetCode 191 Number of 1 Bits（1 比特的數字們）

翻譯

寫一個函數獲取一個無符號整型數，並且返回它的“1”比特的數目（也被叫做Hamming weight）。

例如，一個32位整型數“11”，轉換成二進制是00000000000000000000000000001011，所以這個函數應該返回3。

原文

Write a function that takes an unsigned integer and returns the number of ’1' bits it has (also known as the Hamming weight).

For example, the 32-bit integer ’11' has binary representation 00000000000000000000000000001011, so the function should return 3.

分析

這道題我之前遇到過，這裡就直接貼結果了，稍候我整理一篇關於位運算的博客出來。歡迎大家再來……

代碼

class Solution {
public:
    int hammingWeight(uint32_t n) {
        int count = 0;
        while (n) {
            ++count;
            n = (n - 1) &  n;
        }
        return count;
    }
};