Number of 1 Bits——LeetCode

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.

题目大意：给一个无符号数，返回这个数二进制表示中1的数量。

解题思路：按位和0x1与操作，计算即可。

public int hammingWeight(int n) {
int res = 0;
while(n!=0){
if((n&0x1)==1){
res++;
}
n=n>>>1;
}
return res;
}