The undirected graph is given. Find all its articulation points. \InputFile The first line contains two positive integers $n$ and $m~(n \le 2 \cdot 10^4, m \le 2 \cdot 10^5)$ --- the number of vertices and edges respectively. Each of the next $m$ lines contains the description of an edge. The edge number $i$ is given with two positive integers $b_i, e_i~(1 \le b_i, e_i \le n)$ --- the numbers of the vertices it connects. \OutputFile Print in the first line the number $b$ of articulation points in a given graph. In the next $b$ lines print the numbers of the vertices that are articulation points in increasing order. \includegraphics{https://static.e-olymp.com/content/92/92fc0a17b41de363198e204b09e680ce3e6cd2e9.gif}