Articulation Points - Input Example

Input: $n=5$, edges $[[0,1],[1,2],[2,0],[1,3],[3,4]]$. Graph: triangle $0-1-2-0$ with a tail $1-3-4$. Vertex $1$ is an articulation point. Remove it, and you get components $\{0,2\}$ and $\{3,4\}$. Vertex $3$ is an articulation point.

Remove it, and you get $\{0,1,2\}$ and $\{4\}$. Output: $[1, 3]$. These are the critical vertices holding the graph together. Vertices $0$, $2$, and $4$ are not articulation points.