HDU-1114-Piggy-Bank(完全背包)

#include<iostream>
#include<cstring>
#include<algorithm>
using namespace std;
const int maxn=2*10*1000;
const int inf=0x7f7f7f7f;
int t,e,f,n,m,a,b;
int dp[maxn];
int main()
{
    ios::sync_with_stdio(false);
    cin>>t;
    while(t--)
    {
        memset(dp,0x7f,sizeof(dp));
        cin>>e>>f;
        m=f-e;
        cin>>n;
        dp[0]=0;
        for(int i=0;i<n;i++)
        {
            cin>>a>>b;
            for(int j=b;j<=m;j++)
            {
                dp[j]=min(dp[j],dp[j-b]+a);
            }
        }
        if(dp[m]==inf)
        {
            cout<<"This is impossible."<<endl;
        }
        else
        {
            cout<<"The minimum amount of money in the piggy-bank is "<<dp[m]<<'.'<<endl;
        }
    }
    return 0;
}