题解 | #求int型正整数在内存中存储时1的个数#

import java.util.*;
public class Main {
    public static void main(String args[]) {
        Scanner sc = new Scanner(System.in);
        while (sc.hasNextInt()) {
            int n = sc.nextInt();
            String s = trans(n, 2);
            int yi = 0;
            
            for (int i = 0; i < s.length(); i++) {

                if (s.charAt(i) == '1') {
                    yi++;
                }
               
            }
             System.out.println(yi);
        }
    }
    public static String trans(int num, int radix) {
        StringBuilder sb = new StringBuilder();
        while (num > 0) {
            sb.append(num % radix);
            num /= radix;
        }
        return sb.reverse().toString();
    }
}