HDU 5501 背包问题

需要按照B/C的值从大到小排序。

#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
#include<cmath>
#include<queue>
#include<vector>
#include<map>
using namespace std;
typedef long long LL;
const int INF = 1e9+7;
const int maxn = 1015;
const int MOD = 9973;

int A[maxn], B[maxn], C[maxn];
int dp[3005];
int vis[maxn];

struct node
{
    int A, B, C;
    bool friend operator < (node a, node b)
    {
        return 1.0*a.B/a.C > 1.0*b.B/b.C;
    }
}P[maxn];


int main()
{
    int T;
    scanf("%d",  &T);

    while(T--)
    {
        int n, t;
        scanf("%d %d", &n, &t);
        for(int i=1; i<=n; i++)
            scanf("%d %d %d", &P[i].A, &P[i].B, &P[i].C);

        sort(P+1, P+n+1);
        memset(dp, 0, sizeof(dp));

        for(int i=1; i<= n; i++)
            vis[i] = INF;

        for(int i=1; i<=n; i++)
        {
            for(int j=t; j>=P[i].C; j--)
                dp[j] = max(dp[j], dp[j-P[i].C] + P[i].A - P[i].B*j);
        }

        int ans = 0;
        for(int i=0; i<= t; i++)
            ans = max(ans, dp[i]);

        printf("%d
", ans);
    }
    return 0;
}
/*
1
2 10
110 5 9
30 2 1
*/