|시간 제한||메모리 제한||제출||정답||맞은 사람||정답 비율|
|5 초||128 MB||31||7||1||5.556%|
Thank to cryptography, we are able to encrypt messages such that noone (except the intended recipient) is able to read them. However, encrypted messages are of no use if they do not actually reach the recipient. These days, computer network is the most typical mean to send such messages. In this problem, we will study the issues the networking providers have to solve. And remember: since the message is encrypted, we do not need to care about the network privacy anymore.
The network cables joining computers (servers) belong to different companies. A new antimonopoly legislation prevents any company from owning more than two cables from each server. Furthermore, to avoid wasting resources, there is also a law specifying that the cable system owned by any single company cannot be redundant, i.e., removal of any of the cables will disconnect some two previously connected servers. Since the companies buy and sell the cables all the time, it is quite difficult to enforce these regulations. Your task is to write a program that does so.
The input contains several instances. The first line of each instance contains four integers N, M, C and T separated by spaces — the number of servers (1 ≤ N ≤ 8 000), the number of cables (0 ≤ M ≤ 100 000), the number of companies (1 ≤ C ≤ 100), and the number of cable-selling transactions (0 ≤ T ≤ 100 000), respectively.
The following M lines describe the cables. Each of them contains three integers Sj1, Sj2 and Kj , separated by spaces, giving the numbers of the servers Sj1 and Sj2 (1 ≤ Sj1 < Sj2 ≤ n) joined by that cable and the number of the company Kj (1 ≤ Kj ≤ C) initially owning the cable. For each pair of servers, there is at most one cable joining them. The initial state satisfies the regulations, i.e., each company owns at most two cables incident with each server, and the system of cables owned by a single company has no cycles.
Finally, each of the next T lines contains integers Si1, Si2 and Ki describing one transaction in which the company Ki (1 ≤ Ki ≤ C) tries to buy a cable between servers Si1 and Si2 (1 ≤ Si1 < Si2 ≤ N).
The last instance is followed by a line containing four zeros.
For each input instance, output T lines describing the outcome of the transactions. The possible outcomes are
Print one empty line after each instance.
4 5 3 5 1 2 1 2 3 1 3 4 2 1 4 2 1 3 3 1 2 3 1 2 3 1 4 3 2 3 3 2 4 3 2 1 1 1 1 2 1 1 2 1 0 0 0 0
Sold. Already owned. Forbidden: monopoly. Forbidden: redundant. No such cable. Already owned.