P25935 [AtCoder] Difference of Distance
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题目描述

Problem Statement

We have a connected undirected graph with N vertices numbered 1 to N and M edges numbered 1 to M.
Edge i connects vertex U_i and vertex V_i, and has an integer weight of W_i.
For $1\leq s,t \leq N$,\ $s\neq t$, let us define d(s,t) as follows.

  • For every path connecting vertex s and vertex t, consider the maximum weight of an edge along that path. d(s,t) is the minimum value of this weight.

Answer Q queries. The j-th query is as follows.

  • You are given A_j,S_j,T_j. By what value will d(S_j,T_j) increase when the weight of edge A_j is increased by 1?

Note that each query does not actually change the weight of the edge.

Input

The input is given from Standard Input in the following format:
N M
U_1 V_1 W_1
$\vdots$
U_M V_M W_M
Q
A_1 S_1 T_1
$\vdots$
A_Q S_Q T_Q

Output

Print Q lines.
The $j-th line (1\leq j \leq Q)$ should contain the answer to the j-th query.

Constraints

  • $2\leq N \leq 2\times 10^5$
  • $N-1\leq M \leq 2\times 10^5$
  • $1 \leq U_i,V_i \leq N$
  • $U_i \neq V_i$
  • $1 \leq W_i \leq M$
  • The given graph is connected.
  • $1\leq Q \leq 2\times 10^5$
  • $1 \leq A_j \leq M$
  • $1 \leq S_j,T_j \leq N$
  • $S_j\neq T_j$
  • All values in the input are integers.

Sample Input 1

6 6
1 2 1
3 1 5
4 1 5
3 4 3
5 6 4
2 6 5
7
1 4 6
2 4 6
3 4 6
4 4 6
5 4 6
6 4 6
5 6 5

Sample Output 1

0
0
0
0
0
1
1

The above figure shows the edge numbers in black and the edge weights in blue.
Let us explain the first through sixth queries.
First, consider d(4,6) in the given graph.
The maximum weight of an edge along the path $4 \rightarrow 1 \rightarrow 2 \rightarrow 6$ is 5, which is the minimum over all paths connecting vertex 4 and vertex 6, so d(4,6)=5.
Next, consider the increment of d(4,6) when the weight of edge x\ $(1 \leq x \leq 6)$ increases by 1.
When x=6, we have d(4,6)=6, and the increment is 1. On the other hand, when $x \neq 6$, we have d(4,6)=5, and the increment is 0.
For instance, when x=3, the maximum weight of an edge along the path $4 \rightarrow 1 \rightarrow 2 \rightarrow 6$ is 6, but the maximum weight of an edge along the path $4 \rightarrow 3 \rightarrow 1 \rightarrow 2 \rightarrow 6$ is 5, so d(4,6) is still 5.

Sample Input 2

2 2
1 2 1
1 2 1
1
1 1 2

Sample Output 2

0

The given graph may contain multi-edges.

输入格式

见题面 Input 部分

输出格式

见题面 Output 部分

样例输入
6 6 1 2 1 3 1 5 4 1 5 3 4 3 5 6 4 2 6 5 7 1 4 6 2 4 6 3 4 6 4 4 6 5 4 6 6 4 6 5 6 5
样例输出
0 0 0 0 0 1 1