题解 | #称砝码#,看了别人的才知道可以这么玩，有意思

import java.util.ArrayList;
import java.util.HashSet;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        while (in.hasNextInt()) {
            int n = in.nextInt();
            int[] g = new int[n];
            for (int i = 0; i < g.length; i++) {
                g[i] = in.nextInt();
            }
            int[] number = new int[n];
            for (int i = 0; i < number.length; i++) {
                number[i] = in.nextInt();
            }
            HashSet<Integer> set = new HashSet<>();
            set.add(0);
            // 遍历砝码
            for (int i = 0; i < g.length; i++) {
                ArrayList<Integer> list = new ArrayList<>(set);
                // 遍历个数
                for (int j = 1; j <= number[i]; j++) {
                    // 从一个砝码往上加
                    for (int k = 0; k < list.size(); k++) {
                        // 每个数量的砝码都会去匹配
                        set.add(list.get(k) + g[i] * j);
                    }
                }
            }
            System.out.println(set.size());
        }
    }
}