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HDOJ 4939 Stupid Tower Defense


red放到后面显然更优,dp【i】【j】表示前i个塔里有j个blue,最后枚举有多少个red

Stupid Tower Defense

Time Limit: 12000/6000 MS (Java/Others)    Memory Limit: 131072/131072 K (Java/Others)
Total Submission(s): 599    Accepted Submission(s): 163


Problem Description
FSF is addicted to a stupid tower defense game. The goal of tower defense games is to try to stop enemies from crossing a map by building traps to slow them down and towers which shoot at them as they pass.

The map is a line, which has n unit length. We can build only one tower on each unit length. The enemy takes t seconds on each unit length. And there are 3 kinds of tower in this game: The red tower, the green tower and the blue tower. 

The red tower damage on the enemy x points per second when he passes through the tower.

The green tower damage on the enemy y points per second after he passes through the tower.

The blue tower let the enemy go slower than before (that is, the enemy takes more z second to pass an unit length, also, after he passes through the tower.)

Of course, if you are already pass through m green towers, you should have got m*y damage per second. The same, if you are already pass through k blue towers, the enemy should have took t + k*z seconds every unit length.

FSF now wants to know the maximum damage the enemy can get.
 

Input
There are multiply test cases.

The first line contains an integer T (T<=100), indicates the number of cases. 

Each test only contain 5 integers n, x, y, z, t (2<=n<=1500,0<=x, y, z<=60000,1<=t<=3)
 

Output
For each case, you should output "Case #C: " first, where C indicates the case number and counts from 1. Then output the answer. For each test only one line which have one integer, the answer to this question.
 

Sample Input
1 2 4 3 2 1
 

Sample Output
Case #1: 12
Hint
For the first sample, the first tower is blue tower, and the second is red tower. So, the total damage is 4*(1+2)=12 damage points.
 

Author
UESTC
 

Source
2014 Multi-University Training Contest 7
 




#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>

using namespace std;

typedef long long int LL;

LL n,x,y,z,t;

LL dp[1600][1600];

int main()
{
    int T_T,cas=1;
    scanf("%d",&T_T);
    while(T_T--)
    {
        cin>>n>>x>>y>>z>>t;
        LL ans=0;
        memset(dp,0,sizeof(dp));
        for(LL i=2;i<=n;i++)
        {
            for(LL blue=0;blue<i;blue++)
            {
                if(blue)
                {
                    dp[i][blue]=max(dp[i-1][blue]+(t+blue*z)*(i-blue-1)*y
                                ,dp[i-1][blue-1]+(t+(blue-1)*z)*(i-blue)*y);
                }
                else
                {
                    dp[i][0]=dp[i-1][0]+t*(i-1)*y;
                }
            }
        }
        for(LL red=0;red<=n;red++)
        {
            for(LL blue=0;blue<=n-red;blue++)
            {
                LL green=n-red-blue;
                ans=max(ans,red*(x+green*y)*(blue*z+t)+dp[n-red][blue]);
            }
        }
        printf("Case #%d: %I64d\n",cas++,ans);
    }
    return 0;
}