2127.Xor-matic Number of the Graph

Time Limit: 1s Memory Limit: 256MB

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 \le u \lt v \le 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.

Input Format(From the terminal/stdin)

The first line of the input contains two integers n andm (1 \le n \le 100000, 0 \le m \le 200000)- numbers of vertices and edges in the given graph.

The follow m lines contain three integers ui, vi andti (1 \le ui,vi \le n, 0 \le ti \le 1018, ui \neq vi)- vertices connected by the edge and integer written on it. It is guaranteed that graph doesn't contain self-loops and multiple edges.

Output Format(To the terminal/stdout)

Print the single integer, equal to the described sum over modulo 109+7.

Sample Input 1

Copy
4 4
1 2 1
1 3 2
2 3 3
3 4 1
 · \n
 · · \n
 · · \n
 · · \n
 · · \n

Sample Output 1

Copy
12
  \n

Sample Input 2

Copy
4 4
1 2 1
2 3 2
3 4 4
4 1 8
 · \n
 · · \n
 · · \n
 · · \n
 · · \n

Sample Output 2

Copy
90
  \n

Sample Input 3

Copy
8 6
1 2 2
2 3 1
2 4 4
4 5 5
4 6 3
7 8 5
 · \n
 · · \n
 · · \n
 · · \n
 · · \n
 · · \n
 · · \n

Sample Output 3

Copy
62
  \n

Hints

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.

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