CF724G.Xor-matic Number of the Graph
普及/提高-
通过率:0%
AC君温馨提醒
该题目为【codeforces】题库的题目,您提交的代码将被提交至codeforces进行远程评测,并由ACGO抓取测评结果后进行展示。由于远程测评的测评机由其他平台提供,我们无法保证该服务的稳定性,若提交后无反应,请等待一段时间后再进行重试。
题目描述
You are given an undirected graph, constisting of n vertices and m edges. Each edge of the graph has some non-negative integer written on it.
Let's call a triple (u,v,s) interesting, if 1<=u<v<=n and there is a path (possibly non-simple, i.e. it can visit the same vertices and edges multiple times) between vertices u and v such that xor of all numbers written on the edges of this path is equal to s . When we compute the value s for some path, each edge is counted in xor as many times, as it appear on this path. It's not hard to prove that there are finite number of such triples.
Calculate the sum over modulo 109+7 of the values of s over all interesting triples.
输入格式
The first line of the input contains two integers n and m ( 1<=n<=100000 , 0<=m<=200000 ) — numbers of vertices and edges in the given graph.
The follow m lines contain three integers ui , vi and ti ( 1<=ui,vi<=n , 0<=ti<=1018 , ui=vi ) — vertices connected by the edge and integer written on it. It is guaranteed that graph doesn't contain self-loops and multiple edges.
输出格式
Print the single integer, equal to the described sum over modulo 109+7 .
输入输出样例
输入#1
4 4 1 2 1 1 3 2 2 3 3 3 4 1
输出#1
12
输入#2
4 4 1 2 1 2 3 2 3 4 4 4 1 8
输出#2
90
输入#3
8 6 1 2 2 2 3 1 2 4 4 4 5 5 4 6 3 7 8 5
输出#3
62
说明/提示
In the first example the are 6 interesting triples:
- (1,2,1)
- (1,3,2)
- (1,4,3)
- (2,3,3)
- (2,4,2)
- (3,4,1)
The sum is equal to 1+2+3+3+2+1=12 .In the second example the are 12 interesting triples:
- (1,2,1)
- (2,3,2)
- (1,3,3)
- (3,4,4)
- (2,4,6)
- (1,4,7)
- (1,4,8)
- (2,4,9)
- (3,4,11)
- (1,3,12)
- (2,3,13)
- (1,2,14)
The sum is equal to 1+2+3+4+6+7+8+9+11+12+13+14=90 .