luogu#P9340. [JOISC 2023 Day3] Tourism

[JOISC 2023 Day3] Tourism

题目描述

JOI Kingdom is an insular country consisting of NN islands, numbered from 11 to NN. The islands are connected by N1N − 1 bridges, numbered from 11 to N1N − 1. The bridge i (1iN1)i\ (1 ≤ i ≤ N − 1) connects the island AiA_i and the island BiB_i bidirectionally. It is possible to travel from any island to any other island by passing through a number of bridges. In JOI Kingdom, there are MM sightseeing spots, numbered from 11 to MM. The sightseeing spot j (1jM)j\ (1 ≤ j ≤ M) is located in the island CjC_j. There are QQ travelers. They plan to visit sightseeing spots in JOI Kingdom. The travelers are numbered from 11 to QQ. Each traveler makes a trip in the following way.

  1. The traveler chooses an island x (1xN)x\ (1 ≤ x ≤ N). Taking an airplane, the traveler arrives at the island xx.

  2. The traveler takes the following actions a number of times. The order and the kinds of actions are arbitrary.

    • The traveler chooses a sightseeing spot in the current island, and visits there.
    • The traveler moves to another island by passing through a bridge.
  3. Taking an airplane, the traveler leaves JOI Kingdom. The traveler k (1kQ)k\ (1 ≤ k ≤ Q) wants to visit all of the sightseeing spots Lk,Lk+1,...,RkL_k, L_{k + 1}, . . . , R_k. However, since the budget is limited, the traveler kk wants to minimize the number of islands where the traveler kk visits at least once.

Write a program which, given information of JOI Kingdom and the travelers, calculates, for each k (1kQ)k\ (1 ≤ k ≤ Q), the minimum possible number of islands where the traveler kk​ visits at least once.

输入格式

Read the following data from the standard input.

N M QN\ M\ Q

A1 B1A_1\ B_1

A2 B2A_2\ B_2

\vdots

AN1 BN1A_{N−1}\ B_{N−1}

C1 C2  CMC_1\ C_2\ · · ·\ C_M

L1 R1L_1\ R_1

L2 R2L_2\ R_2

\vdots

LQ RQL_Q\ R_Q

输出格式

Write QQ lines to the standard output. The kk-th line (1kQ)(1 ≤ k ≤ Q) of output should contain the minimum possible number of islands where the traveler kk visits at least once.

题目大意

给出一颗 nn 个节点的树,和一个长度为 mm 的序列 aaqq 次询问包含 alra_{l\cdots r} 中所有节点的最小联通块大小。

n,m,q105n,m,q\le 10^5

7 6 2
1 2
1 3
2 4
2 5
3 6
3 7
2 3 6 4 5 7
1 3
4 6
4
6
8 8 9
1 2
2 3
3 4
4 5
5 6
6 7
7 8
8 6 4 3 5 2 4 7
3 5
4 6
6 8
1 4
2 3
6 8
5 5
2 8
1 2
3
4
6
6
3
6
1
6
3
10 7 9
6 5
3 6
9 3
8 3
7 8
7 1
2 5
7 10
8 4
9 4 10 1 10 7 6
4 4
1 3
1 3
6 7
3 6
3 3
1 5
2 5
1 2
1
6
6
4
3
1
7
5
4

提示

【样例解释 #1】

The traveler 1 makes a trip in the following way, and visits all of the sightseeing spots 1, 2, 3.

  1. The traveler 1 arrives at the island 2.
  2. The traveler 1 visits the sightseeing spot 1 in the island 2.
  3. The traveler 1 moves from the island 2 to the island 1 by passing through the bridge 1.
  4. The traveler 1 moves from the island 1 to the island 3 by passing through the bridge 2.
  5. The traveler 1 visits the sightseeing spot 2 in the island 3.
  6. The traveler 1 moves from the island 3 to the island 6 by passing through the bridge 5.
  7. The traveler 1 visits the sightseeing spot 3 in the island 6.
  8. The traveler 1 departs from the island 6 and leaves JOI Kingdom.

The islands 1, 2, 3, 6 are the four islands where the traveler 1 visits at least once. If the number of islands traveler 1 visits at least once is less than or equal to 3, it is impossible to visit all of the sightseeing spots 1, 2, 3. Therefore, output 4 in the first line. The traveler 2 makes a trip in the following way, and visits all of the sightseeing spots 4, 5, 6.

  1. The traveler 2 arrives at the island 3.
  2. The traveler 2 moves from the island 3 to the island 7 by passing through the bridge 6.
  3. The traveler 2 visits the sightseeing spot 6 in the island 7.
  4. The traveler 2 moves from the island 7 to the island 3 by passing through the bridge 6.
  5. The traveler 2 moves from the island 3 to the island 1 by passing through the bridge 2.
  6. The traveler 2 moves from the island 1 to the island 2 by passing through the bridge 1.
  7. The traveler 2 moves from the island 2 to the island 4 by passing through the bridge 3.
  8. The traveler 2 visits the sightseeing spot 4 in the island 4.
  9. The traveler 2 moves from the island 4 to the island 2 by passing through the bridge 3.
  10. The traveler 2 moves from the island 2 to the island 5 by passing through the bridge 4.
  11. The traveler 2 visits the sightseeing spot 5 in the island 5.
  12. The traveler 2 departs from the island 5 and leaves JOI Kingdom.

The islands 1, 2, 3, 4, 5, 7 are the six islands where the traveler 2 visits at least once. If the number of islands traveler 2 visits at least once is less than or equal to 5, it is impossible to visit all of the sightseeing spots 4, 5, 6. Therefore, output 6 in the second line. This sample input satisfies the constraints of Subtasks 1, 2, 4, 5, 6.

The islands 1, 2, 3, 4, 5, 7 are the six islands where the traveler 2 visits at least once. If the number of islands traveler 2 visits at least once is less than or equal to 5, it is impossible to visit all of the sightseeing spots 4, 5, 6. Therefore, output 6 in the second line.

This sample input satisfies the constraints of Subtasks 1, 2, 4, 5, 6.

【样例解释 #2】

This sample input satisfies the constraints of Subtasks 1, 2, 3, 6.

【样例解释 #3】

This sample input satisfies the constraints of Subtasks 1, 2, 6.

【数据范围】

  • 1N1000001 ≤ N ≤ 100 000.
  • 1M1000001 ≤ M ≤ 100 000.
  • 1Q1000001 ≤ Q ≤ 100 000.
  • 1AiN (1iN1)1 ≤ A_i ≤ N\ (1 ≤ i ≤ N − 1).
  • 1BiN (1iN1)1 ≤ B_i ≤ N\ (1 ≤ i ≤ N − 1).
  • It is possible to travel from any island to any other island by passing through a number of bridges.
  • 1CjN (1jM)1 ≤ C_j ≤ N\ (1 ≤ j ≤ M).
  • 1LkRkM (1kQ)1 ≤ L_k ≤ R_k ≤ M\ (1 ≤ k ≤ Q).
  • Given values are all integers.

【子任务】

  1. (5 points) N300,M300,Q300N ≤ 300, M ≤ 300, Q ≤ 300.
  2. (5 points) N2000,M2000,Q2000N ≤ 2 000, M ≤ 2 000, Q ≤ 2 000.
  3. (7 points) Ai=i,Bi=i+1 (1iN1)A_i = i, B_i = i + 1\ (1 ≤ i ≤ N − 1).
  4. (18 points) $L_1 = 1, R_{k} + 1 = L_{k+1}\ (1 ≤ k ≤ Q − 1), R_Q = M$.
  5. (24 points) $A_i = \lfloor\frac{i+1}2\rfloor, B_i = i + 1\ (1 ≤ i ≤ N−1)$. Here, x⌊x⌋ is the largest integer not exceeding x.
  6. (41 points) No additional constraints.