HDU 1114 Piggy-Bank

题解：完全背包问题（背包要装满）

#include <cstdio>   
using namespace std;  
int e,b,n;  
int f[10005];  
int p[505],w[505];  
int main(){  
    int t;  
    scanf("%d",&t);  
    while(t--){  
        scanf("%d%d",&e,&b);  
        e=b-e;  
        scanf("%d",&n);  
        for(int i=1;i<=n;i++)scanf("%d%d",&p[i],&w[i]);  
        for(int i=1;i<=e;i++)f[i]=1e9;  
        f[0]=0;  
        for(int i=1;i<=n;i++){  
            for(int j=w[i];j<=e;j++){  
                if(f[j-w[i]]+p[i]<f[j])f[j]=f[j-w[i]]+p[i];        
            }     
        }     
        if(f[e]==1e9)printf("This is impossible.\n");  
        else printf("The minimum amount of money in the piggy-bank is %d.\n",f[e]);  
    }  
  
    return 0;     
}