KOICOST - Cost
You are given an undirected graph with N verticies and M edges, where the weights are unique.
There is a function Cost(u, v), which is defined as follows:
While there is a path between vertex u and v, delete the edge with the smallest weight. Cost(u,v) is the sum of the weights of the edges that were deleted in this process.
For example, from the graph above (same as the sample input), Cost(2,6) is 2+3+4+5+6 = 20.
Given an undirected graph, your task is to calculate the sum of Cost(u,v) for all vertices u and v, where u < v. Since the answer can get large, output the answer modulo 10^9.
The first line of the input consists of two integers, N and M. (1 <= N <= 100,000, 0 <= M <= 100,000)
The next M lines consists of three integers, u, v, and w. This means that there is an edge between vertex u and v with weight w. (1 <= u, v <= N, 1 <= w <= 100,000)
Output the sum specified in the problem statement.
Input: 6 7
1 2 10
2 3 2
4 3 5
6 3 15
3 5 4
4 5 3
2 6 6
"While there is a path between vertex u and v, delete the edge with the smallest weight" doesn't imply weight in a given path.
i think its the best question on dsu
Beautiful problem on DSU . Enjoy solving it !!
why sigabrt : (((
I removed SIGSEGV by adding
getting SIGSEGV ....any help?.....perfectly runs on my ide
From TLE in C to AC in pure Python =) Great problem, came upon more ideas just improving my code here than I usually get solving several tasks.
undoubtedly the best mst problem on spoj
Take MOD 10^9 :)