Get a tree

The connected undirected graph without loops and multiple edges is given. You are allowed to remove the edges from it. Obtain a tree from the graph.

Input

The first line contains the number of vertices $n(1\le n\le 100)$ and the number of edges $m$ of the graph. The next $m$ pairs of numbers define the edges. It is guaranteed that the graph is connected.

Output

Print $n-1$ pairs of numbers — the edges that will be included in a tree. The edges can be displayed in any order.

Examples