- Time limit: 1.00 s
- Memory limit: 512 MB
You are given a tree consisting of n nodes.
Your task is to process q queries of the form: what is the distance between nodes a and b?
The first input line contains two integers n and q: the number of nodes and queries. The nodes are numbered 1,2,\ldots,n.
Then there are n-1 lines describing the edges. Each line contains two integers a and b: there is an edge between nodes a and b.
Finally, there are q lines describing the queries. Each line contains two integer a and b: what is the distance between nodes a and b?
Print q integers: the answer to each query.
- 1 \le n, q \le 2 \cdot 10^5
- 1 \le a,b \le n
5 3 1 2 1 3 3 4 3 5 1 3 2 5 1 4
1 3 2