Given a tree of ~N~ nodes, and two paths, one from ~a~ to ~b~ and another from ~c~ to ~d~, find the number of nodes that are part of both paths.

Input Specification

The first line will contain the integer ~N~ ~(1 \le N \le 10^5)~.

The second line will contain four integers, ~a, b, c, d~ ~(1 \le a, b, c, d \le N)~.

The next ~N-1~ lines will each contain two integers, ~u, v~ ~(1 \le u, v \le N)~.

It is guaranteed the entire tree is connected.

Output Specification

Output the number of nodes that are part of both paths.

Sample Input

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

Sample Output

1

Explanation for Sample

Only node ~4~ is part of both paths.