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16.8: Exercises

  • Page ID
    93277
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    Exercise \(\PageIndex{1}\)

    Prove that if a graph contains a closed trail then it also contains a proper cycle.

    Spanning trees.

    For each of the graphs in Exercises 2–3, draw a spanning tree by inspection.

    Exercise \(\PageIndex{2}\)

    clipboard_eb181561a5325de24f789f31a4b646074.png
    Figure \(\PageIndex{1}\)

    Exercise \(\PageIndex{3}\)

    clipboard_e38fab3ded5b016bf7717ea130109379d.png
    Figure \(\PageIndex{2}\)

    Reducing to a spanning tree.

    For each of the graphs in Exercises 4–5, use the following algorithm to obtain a spanning tree.

    • If the graph contains a proper cycle, remove one edge of that cycle.
    • If the resulting subgraph contains a proper cycle, remove one edge of that cycle.
    • If the resulting subgraph contains a proper cycle, remove one edge of that cycle.
    • etc..
    • Continue until there are no proper cycles left.

    Exercise \(\PageIndex{4}\)

    clipboard_eae76bedf050e0e90c819de5a847bcc27.png
    Figure \(\PageIndex{3}\)

    Exercise \(\PageIndex{5}\)

    clipboard_e0326fca7acd6cf19a546e96feeed062d.png
    Figure \(\PageIndex{4}\)

    Depth-first and breadth-first spanning trees.

    For each of the graphs in Exercises 6–8, determine both a depth-first and breadth-first spanning tree. Use any vertex you like as the starting node.

    Exercise \(\PageIndex{6}\)

    clipboard_e9467f72552af2dda72124506cfd64f25.png
    Figure \(\PageIndex{5}\)

    Exercise \(\PageIndex{7}\)

    clipboard_e5eacd659dc637eb67e03ce36d596e4f6.png
    Figure \(\PageIndex{6}\)

    Exercise \(\PageIndex{8}\)

    clipboard_eb459fc9ddadd315f303ed6de777d82fc.png
    Figure \(\PageIndex{7}\)

    This page titled 16.8: Exercises is shared under a GNU Free Documentation License 1.3 license and was authored, remixed, and/or curated by Jeremy Sylvestre via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.