The colorful paths and rainbow paths have been considered by several authors. A colorful directed path in a digraph $G$ is a directed path with $\chi(G)$ vertices whose colors are different. A $v$-colorful directed path is such a directed path, starting from $v$. We prove that for a given $3$-regular triangle-free digraph $G$ determining whether there is a proper $\chi(G)$-coloring of $G$ such that for every $v \in V (G)$, there exists a $v$-colorful directed path is $ \mathbf{NP} $-complete.
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Saqaeeyan, S. , Mollaahmadi, E. and Dehghan, A. (2013). On the complexity of the colorful directed paths in vertex coloring of digraphs. Transactions on Combinatorics, 2(2), 1-7. doi: 10.22108/toc.2013.2840
MLA
Saqaeeyan, S. , , Mollaahmadi, E. , and Dehghan, A. . "On the complexity of the colorful directed paths in vertex coloring of digraphs", Transactions on Combinatorics, 2, 2, 2013, 1-7. doi: 10.22108/toc.2013.2840
HARVARD
Saqaeeyan, S., Mollaahmadi, E., Dehghan, A. (2013). 'On the complexity of the colorful directed paths in vertex coloring of digraphs', Transactions on Combinatorics, 2(2), pp. 1-7. doi: 10.22108/toc.2013.2840
CHICAGO
S. Saqaeeyan , E. Mollaahmadi and A. Dehghan, "On the complexity of the colorful directed paths in vertex coloring of digraphs," Transactions on Combinatorics, 2 2 (2013): 1-7, doi: 10.22108/toc.2013.2840
VANCOUVER
Saqaeeyan, S., Mollaahmadi, E., Dehghan, A. On the complexity of the colorful directed paths in vertex coloring of digraphs. Transactions on Combinatorics, 2013; 2(2): 1-7. doi: 10.22108/toc.2013.2840