Weighted edges of a graph

[cba]

You are given a weighted tree T and an integer MAXW . You have to count the number of weighted graphs whose non-negative edges weigh at most MAXW and T is an MST(minimum spanning tree) for that graph. Print the result modulo 987654319.

Input

First line: Two integers n and MAXW denoting the number of vertices of the given tree and the maximum allowed weight of an edge respectively (1<=n<=300000)
Next N-1 lines: Describes the tree, each of which contains three integers,v,u,w , which means that there is an edge connecting the vertices v and u with a weight equal to w (0<=MAXW,w <=10^9)
It is guaranteed that the given graph forms a tree.
Output
Print only one integer, the number of desired graphs modulo 987654319.

[dhayden]

Please describe what you've done, or how you think you can solve the problem. We won't just solve it for you.

[cba]

I have tried making mst from given tree. While creating mst as I was adding edges I checked it wether it would form a cycle or not. If it will form a cycle then I would find the maximum edge till now i.e current edge. And then multiplying them under modulo m

[ne555]

> I have tried making mst from given tree
the mst of a tree is the tree itself...

> I checked it wether it would form a cycle or not
you have a tree, a tree does not have cycles...

> I would find the maximum edge till now i.e current edge.
an easy search then...

> And then multiplying them under modulo m
wonder how do you multiply edges...


you are not explaining yourself.