Roundgod has a rooted tree with  nodes, and the nodes are indexed from  to .
Wcy has  quries, in each of which three integers are given. You need to calculate how many pairs of  with  whose lowest common ancestor is .

输入描述:

The first line contains three integers , denoting the number of nodes in the tree nodes, the number of queries, and the index of the root respectively.
Each of the next  lines contains two integers , which means an edge between  and .
The following  lines contain the descriptions of the queries. Each has three integers .
It is guaranteed that the given edges form a tree.

输出描述:

Print  lines. The -th line contain single integer for -th query.

10 10 7
4 2
10 4
3 2
6 10
9 2
7 3
1 4
8 2
5 3
8 10 10
2 6 2
3 6 2
4 6 4
3 10 2
8 8 10
3 10 4
2 3 2
2 6 4
1 7 10

0
2
0
1
7
0
2
0
1
0