Number of 1 Bits

public class Solution {
    // you need to treat n as an unsigned value
    public int hammingWeight(int n) {
        int count = 0;
        if(n < 0){
            count = 1;
        }
        else{
            count = 0;
        }
        
        for(int i = 0; i<31; i++){
            if((n & 1<<i)!=0){
                count ++;
            }
        }
        
        return count;
    }
}