HDU 1114 Piggy-Bank

题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=1114

分析：每个物品可以取无限个，完全背包问题，要求装满，所以dp[0]=0,其余为INF；

#include<iostream>
#include<sstream>
#include<cstdio>
#include<cstdlib>
#include<string>
#include<cstring>
#include<algorithm>
#include<functional>
#include<iomanip>
#include<numeric>
#include<cmath>
#include<queue>
#include<vector>
#include<set>
#include<cctype>
#define PI acos(-1.0)
const int INF = 0x3f3f3f3f;
const int NINF = -INF - 1;
const int maxn = 1e4 + 5;
typedef long long ll;
using namespace std;
int cost[505], weight[505];
int dp[maxn];
int main()
{
    int T;
    scanf("%d", &T);
    while (T--)
    {
        int E, F;
        scanf("%d%d", &E, &F);
        int n;
        scanf("%d", &n);
        for (int i = 0; i < n; ++i)
            scanf("%d%d", &cost[i], &weight[i]);
        int ans = F - E;
        for (int i = 0; i <= ans; ++i)
            dp[i] = INF;
        dp[0] = 0;
        for (int i = 0; i < n; ++i)
        {
            for (int j = weight[i]; j <= ans; ++j)
            {
                dp[j] = min(dp[j], dp[j - weight[i]] + cost[i]);
                //cout << j << ' ' << dp[j] << endl;
            }
        }
        if (dp[ans] == INF) printf("This is impossible.
");
        else printf("The minimum amount of money in the piggy-bank is %d.
", dp[ans]);
    }
    return 0;
}