Definition (Cut Vertex)

A cut vertex of is a vertex of such that removing will make it disconnected.

"\\usepackage{tikz-cd}\n\\begin{document}\n\\begin{tikzcd}\n\ta & b & c\n\t\\arrow[no head, from=1-1, to=1-2]\n\t\\arrow[no head, from=1-2, to=1-3]\n\\end{tikzcd}\n\\end{document}"abc
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Here, if is removed, then and are not reachable from each other.