# Bondy, J. Adrian

## Cyclic spanning subdigraph with small cyclomatic number ★★

Author(s): Bondy

\begin{conjecture} Let $D$ be a digraph all of whose strong components are nontrivial. Then $D$ contains a cyclic spanning subdigraph with cyclomatic number at most $\alpha(D)$. \end{conjecture}

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## Switching reconstruction of digraphs ★★

\begin{question} Are there any switching-nonreconstructible digraphs on twelve or more vertices? \end{question}

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