Bob wants to know about his ancestors, therefore, he draws a graph of his family. In that graph, root is the eldest-known family member. The leaf node is a member who has no children.
You are given a \(Q\) query and \(N\) family members. They have to just print the \(k^{th}\) ancestors with respect to that query. A member can have only one parent.
Note: Print -1 if the query is incorrect, that is, if the \(k^{th}\) ancestor is not available. The root of the tree is 1.
Input format
- The first line contains two space-separated integers \(N\) and \(Q\) denoting the number of nodes and the number of queries.
- Next \(N- 1\) lines contain two space-separated integers \(u\) and \(v\) denoting an edge between node \(u\) and node \(v\).
- Next \(Q\) lines contain two space-separated integers \(u\) and \(k\).
Output format
For each query, print a single line containing one integer.
Constraints
In this tree 1st Parent of 4th node is 3 and also 3rd parent is node 1.
For Third Query 1st parent of 6 is root node.
Please login to use the editor
You need to be logged in to access the code editor
Loading...
Please wait while we load the editor
Login to unlock the editorial
Please login to use the editor
You need to be logged in to access the code editor
Loading...
Please wait while we load the editor