spoj#GSS7. Can you answer these queries VII
Can you answer these queries VII
Given a tree with N (N <= 100000) nodes. Each node has a interger value x_i (|x_i| <= 10000).
You have to apply Q (Q <= 100000) operations:
1. 1 a b : answer the maximum contiguous sum (maybe empty,will always larger than or equal to 0 ) from the path a->b ( inclusive ).
2. 2 a b c : change all value in the path a->b ( inclusive ) to c. (|c| <= 10000)
Input
first line consists one interger N.
next line consists N interger x_i.
next N-1 line , each consists two interger u,v , means that node u and node v are connected
next line consists 1 interger Q.
next Q line : 1 a b or 2 a b c .
Output
For each query, output one line the maximum contiguous sum.
Example
Input: 5 -3 -2 1 2 3 1 2 2 3 1 4 4 5 3 1 2 5 2 3 4 2 1 2 5</p>Output: 5 9