The undirected graph is given. Find all its articulation points.
The first line contains two positive integers n and m (n≤2⋅104,m≤2⋅105) — 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 bi,ei (1≤bi,ei≤n) — the numbers of the vertices it connects.
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.