专题三 · 1018

Posted 2022-12-14 suamfadmp

代码及解释

#include <iostream>
#include <climits>
#include <algorithm>

// 完全背包问题
// 应该很简单了，但是一直 WA ＝－＝
// 检查了好几遍，转移方程，循环边界都没问题


const size_t SIZE = 10005;

int p[SIZE];
int w[SIZE];
int dp[SIZE];

int main() 
    int T;
    std::cin>>T;

    while(T--) 
        int V1, V2;
        std::cin >> V1 >> V2;
        int V = V2-V1;

        int N;
        std::cin >> N;
        for(int i = 0; i < N; ++i)
            std::cin >> p[i] >> w[i];

        for(int i = 0; i <= V; ++i)
            dp[i] = INT_MAX;

        dp[0] = 0;
        for(int i = 0; i < N; ++i)
            for(int j = w[i]; j <= V; ++j)
                dp[j] = std::min(dp[j], dp[j-w[i]]+p[i]);

        if(dp[V] == INT_MAX)
            std::cout << "This is impossible." << std::endl;
        else
            std::cout << "The minimum amount of money in the piggy-bank is "
                      << dp[V]
                      << "."
                      << std::endl;