题解 | #神奇的口袋#背包问题求方案数模板题

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int[] dp = new int[41];
        dp[0] = 1;
        for (int i = 0; i < n; i++) {
            int weight = sc.nextInt();
            for (int j = 40; j >= weight; j--) {
                dp[j] += dp[j - weight];
            }
        }
        System.out.println(dp[40]);
    }
}