DFS

 Consider the execution of Depth-First Search (DFS) on a graph G. Analyze the following statements:

  • I. The existence of at least one backward edge during the DFS traversal guarantees that G contains at least one cycle.
  • II. In an undirected graph, DFS can generate forward and cross edges if the graph is disconnected.
  • III. After running DFS on a graph, if a backward edge is found, it is still possible to produce a valid topological sort of its vertices.
  • IV. Cross edges alone are sufficient to guarantee that G contains a cycle.

Which of the following combinations of statements is true?

A) I and III only.

B) I and II only.

C) Only I.

D) II and IV only.

E) None of the above.


Original idea by: Thiago Laitz

Comentários

  1. thiago28 de agosto de 2025 às 16:30

    Este comentário foi removido pelo autor.

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    1. Joao Meidanis30 de agosto de 2025 às 12:57

      Questão interessante, mas tem alguns problemas, tipo não esclarecer suficientemente nas afirmações se o grafo é orientado ou não.

      Excluir

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