查找输入整数二进制中1的个数

import java.util.Scanner;public class Main009 {public static void main(String[] args) {Scanner scan = new Scanner(System.in);          int a = scan.nextInt();          int count = 0;          String str = Integer.toBinaryString(a);          for (int i = 0; i < str.length(); i++) {              if(str.charAt(i)=='1')                  count++;          }           System.out.println(count);    }}

和之前某道题的原理一模一样