Ingress (TSP问题+floy预处理)

该问题描述了一个玩家在手机游戏Ingress中,从家出发到各个点收集XM资源并返回的问题,受到次数和距离限制。给定n个点、m条道路、每个点的XM获取规则及限制条件,求最大可获取的XM总量。解决方案涉及TSP(旅行商问题)和Floyd预处理的动态规划应用。

Ingress

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 102400/65535 K (Java/Others)
Total Submission(s): 440    Accepted Submission(s): 205


 

Problem Description

Brickgao, who profited from your accurate calculating last year, made a great deal of money by moving bricks. Now he became ``gay shy fool'' again and recently he bought an iphone and was deeply addicted into a cellphone game called Ingress. Now he is faced with a problem so he turns to you for help again. We make some slight modifications based on the original rules, so please draw attention to the details below.

There are  portals (indexed from 1 to ) around Brickgao's home, and he can get some substances called XM by hacking the portals. It's known that for each portal , he can get  XM during the first hack, and after each hack, the amount of XM he will get during the next hack will decrease by . If the amount of XM he can get is less than or equal to zero, Brickgao can't get XM from that portal anymore. For the -th portal, if  and he hacks 3 times, he will get 10, 8, 6 XM during each hack.

There are  bidirectional roads between some pairs of portals and between Brickga

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