After a long day at school, Andy went home to visit his favourite tree.
This tree will grow every day. Let's call
the tree on day
. The initial tree is
, which consists of
nodes. Every day, each leaf node will be replaced with a subtree identical to
.
Nodes in the tree will be given indices based on their preorder traversal. Note that the tree given is not necessarily a binary tree.
For example, the following graph shows a possible tree
, followed by
, and followed by an illustration of how nodes in
would be ordered according to its preorder traversal:
This tree has already been growing for
days, meaning the current tree is
. Andy will ask you
queries about the length of the simple path between some pair of nodes
and
.
Recall a simple path is a path that does not have repeating vertices.
Constraints
For all subtasks:




Subtask 1 [10%]

Subtask 2 [60%]

Subtask 3 [30%]
No additional constraints.
Input Specification
The first line contains an integer
, the initial number of nodes in the tree.
The second line contains
integers. The
integer is the father of node
in
. The tree will always be rooted on node
. The indices of the nodes given in input are the indices according to the preorder traversal in
. It is guaranteed that the indices given in input form a valid preorder traversal in
.
The third line contains two integers
and
.
means the tree has been growing for
days, and
means the number of queries Andy will ask.
The following
lines contain two integers
and
, meaning Andy wishes to know the length of the simple path between node
and
.
Output Specification
For each of the
queries, output each answer on one line.
Sample Input 1
Copy
10
1 2 3 4 4 3 3 3 2
0 5
1 5
2 9
5 8
2 6
2 10
Sample Output 1
Copy
4
2
3
3
1
Sample Explanation 1
This is the tree formed:
Sample Input 2
Copy
10
1 2 3 4 4 3 3 3 2
2 5
10 20
15 16
89 99
12 98
100 1
Sample Output 2
Copy
4
2
9
16
10
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