Get a tree#978
A connected undirected graph without loops or multiple edges is given. It is allowed to delete edges from the graph. The goal is to obtain a tree.
The first line contains two integers (1 \leq n \leq 100) and — the number of vertices and the number of edges in the graph. The next pairs of integers represent the edges. It is guaranteed that the graph is connected.
Print n - 1 pairs of integers — the edges that form a tree. The edges can be printed in any order.
Example 1