Submit | All submissions | Best solutions | Back to list |
KOICOST - Cost |
You are given an undirected graph with N vertices 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.
Input
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
Output the sum specified in the problem statement.
Example
Input: 6 7
1 2 10
2 3 2
4 3 5
6 3 15
3 5 4
4 5 3
2 6 6 Output: 256
Added by: | Lawl |
Date: | 2011-06-01 |
Time limit: | 1s |
Source limit: | 50000B |
Memory limit: | 1536MB |
Cluster: | Cube (Intel G860) |
Languages: | All except: ASM64 |
Resource: | 2011 KOI Regional |
hide comments
|
|||||||
2015-08-22 15:44:22 fresh
@chenzheng cost(1, 2) = 2 + 5 + 10, cost(1, 3) = 2, cost(1, 4) = 2 cost(2, 3) = 2, cost(2, 4) = 2 cost(3, 4) = 2 + 5 hence the total sum is 32 |
|||||||
2015-08-17 18:37:10 chenzheng
Who can tell me that when I input: 4 3 1 2 10 2 3 2 3 4 5 why the answer is 32? why not 27? who can tell me in detail? |
|||||||
2015-06-01 19:22:58 Uttam Kanodia
Please update the problem for the Modulo and also the statement seems incomplete in the last line before the "Input" section. |
|||||||
2015-02-24 19:58:26 jkelava6
Thanks! This modulo... |
|||||||
2015-02-24 19:49:50 Marin Kisic
Thanks @Rajat De :) |
|||||||
2015-02-24 11:30:54 Rajat De
You need to output the answer modulo 1000000000 |
|||||||
2015-01-25 14:14:55 Himanshu Dagar
I am unable to see the given picture :( --Francky--> Visible again. Last edit: 2015-01-25 15:01:18 |
|||||||
2013-02-20 06:01:06 suyog patil
standard problem!!! |