Solve the programming task below in a Python markdown code block.
You are given a tree with N vertices.

Here, a tree is a kind of graph, and more specifically, a connected undirected graph with N-1 edges, where N is the number of its vertices.

The i-th edge (1≤i≤N-1) connects Vertices a_i and b_i, and has a length of c_i.
You are also given Q queries and an integer K. In the j-th query (1≤j≤Q):
 - find the length of the shortest path from Vertex x_j and Vertex y_j via Vertex K.

-----Constraints-----
 - 3≤N≤10^5 
 - 1≤a_i,b_i≤N (1≤i≤N-1) 
 - 1≤c_i≤10^9 (1≤i≤N-1) 
 - The given graph is a tree.
 - 1≤Q≤10^5 
 - 1≤K≤N 
 - 1≤x_j,y_j≤N (1≤j≤Q) 
 - x_j≠y_j (1≤j≤Q) 
 - x_j≠K,y_j≠K (1≤j≤Q) 

-----Input-----
Input is given from Standard Input in the following format:  
N  
a_1 b_1 c_1  
:  
a_{N-1} b_{N-1} c_{N-1}
Q K
x_1 y_1
:  
x_{Q} y_{Q}

-----Output-----
Print the responses to the queries in Q lines.

In the j-th line j(1≤j≤Q), print the response to the j-th query.

-----Sample Input-----
5
1 2 1
1 3 1
2 4 1
3 5 1
3 1
2 4
2 3
4 5

-----Sample Output-----
3
2
4

The shortest paths for the three queries are as follows:
 - Query 1: Vertex 2 → Vertex 1 → Vertex 2 → Vertex 4 : Length 1+1+1=3 
 - Query 2: Vertex 2 → Vertex 1 → Vertex 3 : Length 1+1=2 
 - Query 3: Vertex 4 → Vertex 2 → Vertex 1 → Vertex 3 → Vertex 5 : Length 1+1+1+1=4