Count 1 in Binary

Count how many 1 in binary representation of a 32-bit integer.

Example

Given 32, return 1

Given 5, return 2

Given 1023, return 9

 public class Solution {
     /**
      * @param num: an integer
      * @return: an integer, the number of ones in num
      */
     public int countOnes(int num) {
         int count = ;
         for (int i = ; i <= ; i++) {
             if ((num & ) == ) {
                 count++;
             }
             num = (num >> );
         }
         return count;
     }
 };