CF1483D.Useful Edges

普及/提高-

通过率:0%

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题目描述

You are given a weighted undirected graph on nn vertices along with qq triples (u,v,l)(u, v, l) , where in each triple uu and vv are vertices and ll is a positive integer. An edge ee is called useful if there is at least one triple (u,v,l)(u, v, l) and a path (not necessarily simple) with the following properties:

  • uu and vv are the endpoints of this path,
  • ee is one of the edges of this path,
  • the sum of weights of all edges on this path doesn't exceed ll .

Please print the number of useful edges in this graph.

输入格式

The first line contains two integers nn and mm ( 2n6002\leq n\leq 600 , 0mn(n1)20\leq m\leq \frac{n(n-1)}2 ).

Each of the following mm lines contains three integers uu , vv and ww ( 1u,vn1\leq u, v\leq n , uvu\neq v , 1w1091\leq w\leq 10^9 ), denoting an edge connecting vertices uu and vv and having a weight ww .

The following line contains the only integer qq ( 1qn(n1)21\leq q\leq \frac{n(n-1)}2 ) denoting the number of triples.

Each of the following qq lines contains three integers uu , vv and ll ( 1u,vn1\leq u, v\leq n , uvu\neq v , 1l1091\leq l\leq 10^9 ) denoting a triple (u,v,l)(u, v, l) .

It's guaranteed that:

  • the graph doesn't contain loops or multiple edges;
  • all pairs (u,v)(u, v) in the triples are also different.

输出格式

Print a single integer denoting the number of useful edges in the graph.

输入输出样例

  • 输入#1

    4 6
    1 2 1
    2 3 1
    3 4 1
    1 3 3
    2 4 3
    1 4 5
    1
    1 4 4

    输出#1

    5
  • 输入#2

    4 2
    1 2 10
    3 4 10
    6
    1 2 11
    1 3 11
    1 4 11
    2 3 11
    2 4 11
    3 4 9

    输出#2

    1
  • 输入#3

    3 2
    1 2 1
    2 3 2
    1
    1 2 5

    输出#3

    2

说明/提示

In the first example each edge is useful, except the one of weight 55 .

In the second example only edge between 11 and 22 is useful, because it belongs to the path 121-2 , and 101110 \leq 11 . The edge between 33 and 44 , on the other hand, is not useful.

In the third example both edges are useful, for there is a path 12321-2-3-2 of length exactly 55 . Please note that the path may pass through a vertex more than once.

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