#P3577. [POI2014] TUR-Tourism

[POI2014] TUR-Tourism

题目描述

King Byteasar believes that Byteotia, a land full of beautiful sights, should attract lots of tourists, who should spend lots of money, which should eventually find their way to the royal treasury.

But reality does not live up to his dream.

So the king instructed his councilor to look into this issue.

The councilor found out that foreigners keep away from Byteotia due to its sparse road network.

Let us remark that there are nn towns in Byteotia, connected by mm two way roads, each road linking two different towns.

The roads may lead through picturesque overflies and somewhat less picturesque tunnels.

There is no guarantee that every town can be reached from every other town.

The councilor observed that the current road network does not allow for a long journey.

Namely, wherever one starts the journey, it is impossible to visit more than 10 towns without passing through some town twice.

Due to limited funds in the treasury, no new roads will be constructed at the time.

Instead, Byteasar has decided to build a network of tourist information points (TIPs), staffed by officers who are to advertise the short trips that are available.

For each town, there should be a TIP either in this town or one of the towns directly linked by a road.

Moreover, the cost of building the TIP is known for each town.

Help the king by finding the cheapest way of building TIPs that will satisfy aforementioned condition.

输入格式

The first line of the standard input contains two integers nn, mm (2n20 0002\le n\le 20\ 000 ,0m25 0000\le m\le 25\ 000), separated by a single space, that specify the number of towns and roads in Byteotia respectively.

The towns are numbered from 11 to nn.

The second line of input contains nn integers c1,c2,,cnc_1,c_2,\cdots,c_n (0ci10 0000\le c_i\le 10\ 000), separated by single spaces; the number cic_i specifies the cost of building a TIP in the town no. ii.

Then, a description of the Byteotian road network follows. The ii-th of the following mm lines contains two integers aia_i,bib_i (1ai<bin1\le a_i<b_i\le n), separated by a single space, that indicate that the towns no. aia_i and bib_i are linked by a road. There is at most one (direct) road between any pair of towns.

输出格式

Your program should print out one integer to the standard output: the total cost of building all the TIPs.

题目大意

给定一个 nn 个点,mm 条边的无向图,其中你在第 ii 个点建立旅游站点的费用为 CiC_i。在这张图中,任意两点间不存在节点数超过 1010 的简单路径。请找到一种费用最小的建立旅游站点的方案,使得每个点要么建立了旅游站点,要么与它有边直接相连的点里至少有一个点建立了旅游站点。

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