2934.Misha and LCP on Tree

Time Limit: 1s Memory Limit: 256MB

Misha has a tree with characters written on the vertices. He can choose two vertices s and t of this tree and write down characters of vertices lying on a path from s to t. We'll say that such string corresponds to pair (s,t).

Misha has m queries of type: you are given 4 vertices a, b, c, d; you need to find the largest common prefix of the strings that correspond to pairs (a,b) and (c,d). Your task is to help him.

Input Format(From the terminal/stdin)

The first line contains integer n (1 \le n \le 300000) - the number of vertices in the tree.

Next follows a line consisting of n small English letters. The i-th character of the string corresponds to the character written on the i-th vertex.

Next n-1 lines contain information about edges. An edge is defined by a pair of integers u, v (1 \le u,v \le n, u \neq v), separated by spaces.

The next line contains integer m (1 \le m \le 1000000) - the number of queries.

Next m lines contain information about queries. A query is defined by four integers a, b, c, d (1 \le a,b,c,d \le n), separated by spaces.

Output Format(To the terminal/stdout)

For each query print the length of the largest common prefix on a separate line.

Sample Input

Copy
6
bbbabb
2 1
3 2
4 3
5 2
6 5
6
2 5 3 1
1 5 2 3
5 6 5 6
6 3 4 1
6 2 3 4
2 2 4 5
 \n
      \n
 · \n
 · \n
 · \n
 · \n
 · \n
 \n
 · · · \n
 · · · \n
 · · · \n
 · · · \n
 · · · \n
 · · · \n

Sample Output

Copy
2
2
2
0
1
0
 \n
 \n
 \n
 \n
 \n
 \n

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