11
22
2015
2

[Codeforces Round #326] Duff in the Army


E. Duff in the Army
time limit per test
4 seconds
memory limit per test
512 megabytes
input
standard input
output
standard output

Recently Duff has been a soldier in the army. Malek is her commander.

Their country, Andarz Gu has n cities (numbered from 1 to n) and n - 1 bidirectional roads. Each road connects two different cities. There exist a unique path between any two cities.

There are also m people living in Andarz Gu (numbered from 1 to m). Each person has and ID number. ID number of i - th person is iand he/she lives in city number ci. Note that there may be more than one person in a city, also there may be no people living in the city.

Malek loves to order. That's why he asks Duff to answer to q queries. In each query, he gives her numbers v, u and a.

To answer a query:

Assume there are x people living in the cities lying on the path from city v to city u. Assume these people's IDs are p1, p2, ..., px in increasing order.

If k = min(x, a), then Duff should tell Malek numbers k, p1, p2, ..., pk in this order. In the other words, Malek wants to know a minimums on that path (or less, if there are less than a people).

Duff is very busy at the moment, so she asked you to help her and answer the queries.

Input

The first line of input contains three integers, n, m and q (1 ≤ n, m, q ≤ 105).

The next n - 1 lines contain the roads. Each line contains two integers v and u, endpoints of a road (1 ≤ v, u ≤ nv ≠ u).

Next line contains m integers c1, c2, ..., cm separated by spaces (1 ≤ ci ≤ n for each 1 ≤ i ≤ m).

Next q lines contain the queries. Each of them contains three integers, v, u and a (1 ≤ v, u ≤ n and 1 ≤ a ≤ 10).

Output

For each query, print numbers k, p1, p2, ..., pk separated by spaces in one line.

Sample test(s)
input
5 4 5
1 3
1 2
1 4
4 5
2 1 4 3
4 5 6
1 5 2
5 5 10
2 3 3
5 3 1
output
1 3
2 2 3
0
3 1 2 4
1 2
Note

Graph of Andarz Gu in the sample case is as follows (ID of people in each city are written next to them):

题目大意:有n个城市,形成一棵树,有若干个人,按照输入顺序编号,给出它们所在的城市。有q个询问,对于每个询问$\left(u,v\right)$输出在城市u、v之间的最短路径上的所有城市中编号最小的a个人。


因为a最大只有10,所以可以在做倍增LCA的预处理时处理出路径上编号最小的10个人,在查询时进行合并就行了。

代码在此。

Category: 题解 | Tags: Codeforces LCA 倍增 | Read Count: 595
Avatar_small
qiancl 说:
Nov 23, 2015 09:12:10 PM

艹。。然而我当时写的是dfs序主席树


登录 *


loading captcha image...
(输入验证码)
or Ctrl+Enter

Host by is-Programmer.com | Power by Chito 1.3.3 beta | Theme: Aeros 2.0 by TheBuckmaker.com