Write a function that takes an unsigned integer and returns the number of '1' bits it has (also known as the Hamming weight).
Example 1:
Input: 11
Output: 3
Explanation: Integer 11 has binary representation 00000000000000000000000000001011
分析:
返回一个无符号整数二进制中位1的个数。依次按位与1,若结果为1,则个数num+1,直至32位全部比较完即可。
class Solution {
public:
int hammingWeight(uint32_t n) {
int num = 0;
for(int i=0; i<32; i++)
{
if(n & 1 == 1)
num++;
n = n>>1;
}
return num;
}
};