Connection Points 2

Given an undirected graph, your task is to identify all the articulation points within it.

Input

The first line contains two natural numbers, n and m, representing the number of vertices and edges in the graph, respectively (n ≤ 620,000, m ≤ 6,200,000). The following m lines each describe an edge with two natural numbers b[i] and e[i] (1 ≤ b[i], e[i] ≤ n), which are the endpoints of the edge.

Output

First, output the number of articulation points b in the graph. Then, on the next line, list b integers representing the vertex numbers that are articulation points, sorted in ascending order.

Examples