题解 | #称砝码#

// HJ41-3 称砝码.cpp : 此文件包含 "main" 函数。程序执行将在此处开始并结束。
#include<iostream>
#include<bits/stdc++.h>

using namespace std;

int main()
{
	int n;
	
	while (cin >> n)
	{
		vector<int>weight(n);
		vector<int>num(n);
		int sum = 0;
		for (int i = 0; i < n; i++)
		{
			cin >> weight[i];
		}
		for (int i = 0; i < n; i++)
		{
			cin >> num[i];
			sum += weight[i] * num[i];
		}
		vector<int>flag(sum + 1, 0);
		flag[0] = 1;
		for (int i = 0; i < n; i++)
		{
			for (int j = 0; j < num[i]; j++)
			{
				for (int k = sum; k >= weight[i]; k--)
				{
					if (flag[k - weight[i]])
					{
						flag[k] = 1;
					}
				}
			}
		}
		int count = 0;
		for (auto c : flag)
		{
			if (c)
			{
				count++;
			}
		}
		cout << count << endl;
	}
	return 0;
}