题解 | #求int型正整数在内存中存储时1的个数#

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int num = in.nextInt();
        char[] charArray = Integer.toBinaryString(num).toCharArray();
        int count = 0;
        for (int i = 0; i < charArray.length; i++) {
            if (charArray[i] == '1') {
                count++;
            }
        }
        System.out.println(count);
    }
}