- Time limit: 1.00 s
- Memory limit: 512 MB
Your task is to process $q$ queries of the form: what is the distance between nodes $a$ and $b$?
Input
The first input line contains two integers $n$ and $q$: the number of nodes and queries. The nodes are numbered $1,2,\ldots,n$.
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 $b$?
Output
Print $q$ integers: the answer to each query.
Constraints
- $1 \le n, q \le 2 \cdot 10^5$
- $1 \le a,b \le n$
Input:
5 3
1 2
1 3
3 4
3 5
1 3
2 5
1 4
Output:
1
3
2