CF1320E.Treeland and Viruses

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时间限制:3.00s

内存限制:512MB

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题目描述

There are nn cities in Treeland connected with n−1n - 1 bidirectional roads in such that a way that any city is reachable from any other; in other words, the graph of cities and roads is a tree. Treeland is preparing for a seasonal virus epidemic, and currently, they are trying to evaluate different infection scenarios.

In each scenario, several cities are initially infected with different virus species. Suppose that there are kik_i virus species in the ii-th scenario. Let us denote vjv_j the initial city for the virus jj, and sjs_j the propagation speed of the virus jj. The spread of the viruses happens in turns: first virus 11 spreads, followed by virus 22, and so on. After virus kik_i spreads, the process starts again from virus 11.

A spread turn of virus jj proceeds as follows. For each city xx not infected with any virus at the start of the turn, at the end of the turn it becomes infected with virus jj if and only if there is such a city yy that:

  • city yy was infected with virus jj at the start of the turn;
  • the path between cities xx and yy contains at most sjs_j edges;
  • all cities on the path between cities xx and yy (excluding yy) were uninfected with any virus at the start of the turn.

Once a city is infected with a virus, it stays infected indefinitely and can not be infected with any other virus. The spread stops once all cities are infected.

You need to process qq independent scenarios. Each scenario is described by kik_i virus species and mim_i important cities. For each important city determine which the virus it will be infected by in the end.

Treeland 有 nn 座城市,由 n−1n - 1 条双向道路连接,使得任意城市均可从其余任一城市到达;换言之,城市与道路构成一棵树。Treeland 正在为季节性病毒疫情做准备,目前正尝试评估多种感染情景。

在每种情景中,若干城市初始时被不同种类的病毒所感染。设第 ii 种情景中共有 kik_i 种病毒。记 vjv_j 为病毒 jj 的初始感染城市,sjs_j 为其传播速度。病毒的传播按轮次进行:先由病毒 11 传播,接着是病毒 22,依此类推;当病毒 kik_i 完成一轮传播后,下一轮再次从病毒 11 开始。

病毒 jj 的一次传播轮次按如下方式进行:对于每个在本轮开始时尚未被任何病毒感染的城市 xx,若满足以下全部条件,则在本轮结束时它将被病毒 jj 感染:

  • 城市 yy 在本轮开始时已被病毒 jj 感染;
  • 城市 xx 与 yy 之间的路径上至多包含 sjs_j 条边;
  • 城市 xx 与 yy 之间路径上的所有城市(不包括 yy)在本轮开始时均未被任何病毒感染。

一旦某城市被某种病毒感染,它将永久保持该病毒感染状态,且不能再被其他病毒所感染。当所有城市均已被感染时,传播过程终止。

你需要处理 qq 个相互独立的情景。每个情景由 kik_i 种病毒及 mim_i 个重要城市描述。对每个重要城市,请确定其最终被哪种病毒所感染。

输入格式

The first line contains a single integer nn (1≤n≤2⋅1051 \leq n \leq 2 \cdot 10^5) — the number of cities in Treeland.

The following n−1n - 1 lines describe the roads. The ii-th of these lines contains two integers xix_i and yiy_i (1≤xi,yi≤n1 \leq x_i, y_i \leq n) — indices of cities connecting by the ii-th road. It is guaranteed that the given graph of cities and roads is a tree.

The next line contains a single integer qq (1≤q≤2⋅1051 \leq q \leq 2 \cdot 10^5) — the number of infection scenarios. qq scenario descriptions follow.

The description of the ii-th scenario starts with a line containing two integers kik_i and mim_i (1≤ki,mi≤n1 \leq k_i, m_i \leq n) — the number of virus species and the number of important cities in this scenario respectively. It is guaranteed that ∑i=1qki\sum_{i = 1}^ q k_i and ∑i=1qmi\sum_{i = 1}^ q m_i do not exceed 2⋅1052 \cdot 10^5.

The following kik_i lines describe the virus species. The jj-th of these lines contains two integers vjv_j and sjs_j (1≤vj≤n1 \leq v_j \leq n, 1≤sj≤1061 \leq s_j \leq 10^6) – the initial city and the propagation speed of the virus species jj. It is guaranteed that the initial cities of all virus species within a scenario are distinct.

The following line contains mim_i distinct integers u1,…,umiu_1, \ldots, u_{m_i} (1≤uj≤n1 \leq u_j \leq n) — indices of important cities.

第一行包含一个整数 nn(1≤n≤2⋅1051 \leq n \leq 2 \cdot 10^5)—— 表示 Treeland 中的城市数量。

接下来的 n−1n - 1 行描述道路。其中第 ii 行包含两个整数 xix_i 和 yiy_i(1≤xi,yi≤n1 \leq x_i, y_i \leq n)—— 表示由第 ii 条道路连接的两座城市的编号。保证所给的城市与道路构成的图是一棵树。

下一行包含一个整数 qq(1≤q≤2⋅1051 \leq q \leq 2 \cdot 10^5)—— 表示感染场景的数量。随后是 qq 个场景的描述。

第 ii 个场景的描述以一行开始,该行包含两个整数 kik_i 和 mim_i(1≤ki,mi≤n1 \leq k_i, m_i \leq n)—— 分别表示该场景中病毒种类的数量和重要城市的数量。保证 ∑i=1qki\sum_{i = 1}^ q k_i 和 ∑i=1qmi\sum_{i = 1}^ q m_i 均不超过 2⋅1052 \cdot 10^5。

接下来的 kik_i 行描述病毒种类。其中第 jj 行包含两个整数 vjv_j 和 sjs_j(1≤vj≤n1 \leq v_j \leq n,1≤sj≤1061 \leq s_j \leq 10^6)—— 分别表示病毒种类 jj 的初始城市及其传播速度。保证同一场景中所有病毒种类的初始城市互不相同。

接下来的一行包含 mim_i 个互不相同的整数 u1,…,umiu_1, \ldots, u_{m_i}(1≤uj≤n1 \leq u_j \leq n)—— 表示重要城市的编号。

输出格式

Print qq lines. The ii-th line should contain mim_i integers — indices of virus species that cities u1,…,umiu_1, \ldots, u_{m_i} are infected with at the end of the ii-th scenario.

输出 qq 行。第 ii 行应包含 mim_i 个整数——即在第 ii 个场景结束时,城市 u1,…,umiu_1, \ldots, u_{m_i} 所感染的病毒种类的编号。

输入输出样例

  • 输入#1

    7
    1 2
    1 3
    2 4
    2 5
    3 6
    3 7
    3
    2 2
    4 1
    7 1
    1 3
    2 2
    4 3
    7 1
    1 3
    3 3
    1 1
    4 100
    7 100
    1 2 3

    输出#1

    1 2
    1 1
    1 1 1

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