Leetcode: 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.

 1 public class Solution {
 2     // you need to treat n as an unsigned value
 3     public int hammingWeight(int n) {
 4         int count = 0;
 5         for (int i=0; i<32; i++) {
 6             if ((n>>>i & 1) == 1) count++;
 7         }
 8         return count;
 9     }
10 }