题目1454：Piggy-Bank

#include <iostream>
#include <algorithm>
#include <queue>
#include <vector>
#include <cstring>
#include <string>
#include <string.h>
#include <stdio.h>
#include <cmath>
#include <map>
#include <functional>
#include <set>
using namespace std;
//1454
const int INF=0x7FFFFFF;
int t,e,f,n,p,w;
int v;
int dp[10010];
struct node{
    int p,w;
}N[500];
int main(){
    //freopen("input.txt","r",stdin);
    while(cin>>t){
        while(t--){
            cin>>e>>f>>n;
            v=f-e;
            for(int i=1;i<=n;i++){
                cin>>N[i].p>>N[i].w;
            }
            for(int i=1;i<=v;i++)
                dp[i]=INF;      //因为要求正好装满，所以初始化0件物品背包容量不为0时为无穷
            dp[0]=0;
            for(int i=1;i<=n;i++){
                for(int j=N[i].w;j<=v;j++){
                    dp[j]=min(dp[j],dp[j-N[i].w]+N[i].p);
                }
            }
            if(dp[v]!=INF)
                cout<<"The minimum amount of money in the piggy-bank is "<<dp[v]<<"."<<endl;
            else
                cout<<"This is impossible."<<endl;
        }
    }
    return 0;
}
/**************************************************************
    Problem: 1454
    User: cust123
    Language: C++
    Result: Accepted
    Time:50 ms
    Memory:1560 kb
****************************************************************/