Олимпиадный тренинг

Задача . K. Keen Tree Calculation


There is a tree of \(N\) vertices and \(N-1\) edges. The \(i\)-th edge connects vertices \(U_i\) and \(V_i\) and has a length of \(W_i\).

Chaneka, the owner of the tree, asks you \(Q\) times. For the \(j\)-th question, the following is the question format:

  • \(X_j\) \(K_j\) – If each edge that contains vertex \(X_j\) has its length multiplied by \(K_j\), what is the diameter of the tree?

Notes:

  • Each of Chaneka's question is independent, which means the changes in edge length do not influence the next questions.
  • The diameter of a tree is the maximum possible distance between two different vertices in the tree.
Input

The first line contains a single integer \(N\) (\(2\leq N\leq10^5\)) — the number of vertices in the tree.

The \(i\)-th of the next \(N-1\) lines contains three integers \(U_i\), \(V_i\), and \(W_i\) (\(1 \leq U_i,V_i \leq N\); \(1\leq W_i\leq10^9\)) — an edge that connects vertices \(U_i\) and \(V_i\) with a length of \(W_i\). The edges form a tree.

The \((N+1)\)-th line contains a single integer \(Q\) (\(1\leq Q\leq10^5\)) — the number of questions.

The \(j\)-th of the next \(Q\) lines contains two integers \(X_j\) and \(K_j\) as described (\(1 \leq X_j \leq N\); \(1 \leq K_j \leq 10^9\)).

Output

Output \(Q\) lines with an integer in each line. The integer in the \(j\)-th line represents the diameter of the tree on the \(j\)-th question.

Note

In the first example, the following is the tree without any changes.

The following is the tree on the \(1\)-st question.

The maximum distance is between vertices \(6\) and \(7\), which is \(6+6+6=18\), so the diameter is \(18\).

The following is the tree on the \(2\)-nd question.

The maximum distance is between vertices \(2\) and \(6\), which is \(3+2+6=11\), so the diameter is \(11\).


Примеры
Входные данныеВыходные данные
1 7
5 1 2
1 4 2
3 4 1
2 5 3
6 1 6
4 7 2
2
4 3
3 2
18
11
2 3
1 2 1000000000
2 3 1000000000
1
2 1000000000
2000000000000000000

time 2000 ms
memory 512 Mb
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