题解 | #求int型正整数在内存中存储时1的个数#

import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int num = scanner.nextInt();
        String s = Integer.toBinaryString(num);
        int count = 0;
        for (int i = 0; i < s.length(); i++) {
            if(s.charAt(i)=='1'){
                count++;
            }
        }
        System.out.println(count);
        scanner.close();
    }
}