An undirected graph is given. Find all of its articulation points.
The first line contains two integers and m~(n \le 2 \cdot 10^4, m \le 2 \cdot 10^5) — the number of vertices and the number of edges in the graph.
Each of the next lines describes an edge and contains two integers b_i and e_i~(1 \le b_i, e_i \le n) — the endpoints of the -th edge.
In the first line, print an integer — the number of articulation points in the graph.
Then print integers — the numbers of the vertices that are articulation points, in increasing order, one per line.

Example 1