Leetcode: 191. Number of 1 Bits(JAVA)

【问题描述】

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】
从最低位按位与，计数器相加即可。

public static int hammingWeight(int n) {
int count = 0;
while (n != 0) {
count += n&1;
n >>>= 1;
}
return count;
}