P25922 [AtCoder] Minimum Reachable City
提高
题目描述

Problem Statement

We have a directed graph G_S with N vertices numbered 1 to N.
It has N-1 edges. The $i-th edge (1\leq i \leq N-1)$ goes from vertex p_i\ $(1\leq p_i \leq i)$ to vertex i+1.
We have another directed graph G with N vertices numbered 1 to N.
Initially, G equals G_S.
Process Q queries on G in the order they are given. There are two kinds of queries as follows.

  • 1 u v : Add an edge to G that goes from vertex u to vertex v.
    It is guaranteed that the following conditions are satisfied.
  • $u \neq v$.
  • On G_S, vertex u is reachable from vertex v via some edges.

  • 2 x : Print the smallest vertex number of a vertex reachable from vertex x via some edges on G (including vertex x).

Input

The input is given from Standard Input in the following format:
N
$p_1 p_2 \dots p_{N-1}$
Q
$\mathrm{query}_1$
$\mathrm{query}_2$
$\vdots$
$\mathrm{query}_Q$

Here, $\mathrm{query}_i$ denotes the i-th query and is in one of the following formats:
1 u v

2 x

Output

Print q lines, where q is the number of queries in the second format.
The $i-th line (1\leq j \leq q)$ should contain the answer to the j-th query in the second format.

Constraints

  • $2\leq N \leq 2\times 10^5$
  • $1\leq Q \leq 2\times 10^5$
  • $1\leq p_i\leq i$
  • For each query in the first format:
  • $1\leq u,v \leq N$.
  • $u \neq v$.
  • On G_S, vertex u is reachable from vertex v via some edges.

  • For each query in the second format, $1\leq x \leq N$.

  • All values in the input are integers.

Sample Input 1

5
1 2 3 3
5
2 4
1 4 2
2 4
1 5 1
2 4

Sample Output 1

4
2
1

  • At the time of the first query, only vertex 4 is reachable from vertex 4 via some edges on G.
  • At the time of the third query, vertices 2, 3, 4, and 5 are reachable from vertex 4 via some edges on G.
  • At the time of the fifth query, vertices 1, 2, 3, 4, and 5 are reachable from vertex 4 via some edges on G.

Sample Input 2

7
1 1 2 2 3 3
10
2 5
1 5 2
2 5
1 2 1
1 7 1
1 6 3
2 5
2 6
2 1
1 7 1

Sample Output 2

5
2
1
1
1

输入格式

见题面 Input 部分

输出格式

见题面 Output 部分

样例输入
5 1 2 3 3 5 2 4 1 4 2 2 4 1 5 1 2 4
样例输出
4 2 1