[leetcode] Number of 1 Bits

Number of 1 Bits

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.

思路：

最基本的位运算，每次移除一位判断是不是1

题解：

class Solution {
public:
int hammingWeight(uint32_t n) {
int res = 0;
for(int i=0;i<32;i++) {
if(n&0x01)
res++;
n = n>>1;
}
return res;
}
};

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