题解 | #完全数计算#

import java.util.*;

// 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 sc = new Scanner(System.in);
        int n = sc.nextInt();
        int count = 1;
        List<Integer> list = new ArrayList<>();
        for (int j = 1; j <= n; j++) {
            Integer sum = 0;
            for (int i = 1; i <= j; i++) {
                if (j % i == 0) {
                    list.add(i);
                }
            }
            Iterator<Integer> iterator = list.iterator();
            while (iterator.hasNext()) {
                sum = sum + iterator.next();
            }
            if (sum / j == 2) {
                count++;
            }
        }
        System.out.println(count);
    }
}