11566 - Tree distance   

Description

Calculate the distance between two nodes.

Input

For each case, the first line contains a positive integer N (1 <= N <= 1000), denoting the number of node in the tree (labeled from 1 to N). The second line contains exactly N numbers. The first number denotes the parent of node 1, and the second number denotes the parent of node 2 ..., etc. The root will be labeled as -1.
For example, sample input

3

-1 1 1

node 1 is root.

The parent of node 2 is node 1.

The parent of node 3 is node 1.

 

Then follows multiple lines of query (query < 10000). Each line contains two positive integers A and B. The query is terminated by two zeros.

Do not assume it is a binary tree.

Output

For each case a line, print the case number first, then output the distance between A and B for each query. Each answer should be separated by a single space.

Sample Input  Download

Sample Output  Download

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