403223: GYM101081 F Auction of Services

Memory Limit:256 MB Time Limit:2 S
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Description

F. Auction of Servicestime limit per test2 secondsmemory limit per test256 megabytesinputstandard inputoutputstandard output

It is becoming more common to use strategies based on social networks for shopping, contract services, arrange meetings, etc. Such strategies often involve interesting mathematical knowledge, like Game Theory. A new trend has appeared, the use of social networks to carry out virtual auctions to contract services. The service providers have agreements between them that enforce a service to cost a predetermine value. The prices a company charges, when it works in collaboration with each of its partners, can be very different, since many factors such as location, previous partnerships, tradition, etc. influence the convenience of a particular partnership.

In this problem you want to estimate the price of a service given by a couple of service providers. It is already known the price of the service given by some companies that have an agreement to work together. Furthermore, if we have two companies A and B, we can contract a service (offered by them) using a chain of companies c1, c2, ... ck, such that

  • ci and ci + 1 have an agreement, for i = 1, ..., k - 1,
  • c1 = A and ck = B.

Also, we know that the price to contract such chain of companies, is the highest price of a service given by a pair of adjacent companies in that chain. That's the power of social networks!

In the previous figure, despite the fact that the price of the agreement between A and C is 13, the best price (in the network that links these companies) is 9, using the agreements through B.

Your task is to help these virtual auctions. The person interested in contracting a certain service chooses a pair of companies he want to contract, and you need to make a program that answers the minimum possible price of that service.

Input

The first line contains two integers N and M, the number of companies and agreements, respectively. The companies are numbered from 1 to N. Each of the following M lines contains three integers, the ith contains Ai, Bi and Ci, indicating that there is an agreement between companies Ai and Bi whose price is Ci. Each pair of companies has at most one agreement. It is guaranteed it is possible to contract a service between any pair of companies.

The next line contains an integer Q, the number of queries. The following Q lines contain a pair of integers representing the companies which we want to contract.

Limits

  • 2 ≤ N ≤ 105
  • 1 ≤ M ≤ 2·105
  • 1 ≤ Ai ≠ Bi ≤ N
  • 1 ≤ Ci ≤ 106
  • 1 ≤ Q ≤ 2·105
Output

Print Q integers representing the price of the service for each query.

ExamplesInput
4 4
1 2 6
1 3 1
2 4 2
3 4 2
2
1 2
1 4
Output
2
2
Input
4 4
1 2 1
2 3 7
2 4 3
3 4 4
4
1 3
1 4
3 2
4 2
Output
4
3
4
3

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