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 fzhinput = new Scanner(System.in);
        int sj = fzhinput.nextInt();
        String ejzsz = Integer.toBinaryString(sj);
        int i,num=0;
        for(i=0;i<ejzsz.length();i++){
            if(ejzsz.charAt(i)=='1'){
                num++;
            }
        }
        System.out.println(num);
    }
}