#5668. CSES1137 子树查询
CSES1137 子树查询
Subtree Queries
You are given a rooted tree consisting of n nodes. The nodes are numbered 1,2,\ldots,n, and node 1 is the root. Each node has a value. Your task is to process following types of queries:
change the value of node s to x
calculate the sum of values in the subtree of node s
Input
The first input line contains two integers n and q: the number of nodes and queries. The nodes are numbered 1,2,\ldots,n. The next line has n integers v_1,v_2,\ldots,v_n: the value of each node. Then there are n-1 lines describing the edges. Each line contans two integers a and b: there is an edge between nodes a and b. Finally, there are q lines describing the queries. Each query is either of the form "1 s x" or "2 s".
Output
Print the answer to each query of type 2.
Constraints
Example
Input
5 3
4 2 5 2 1
1 2
1 3
3 4
3 5
2 3
1 5 3
2 3
Output
8
10