Long directed rainbow cycles and rainbow spanning trees

  title={Long directed rainbow cycles and rainbow spanning trees},
  author={Frederik Benzing and Alexey Pokrovskiy and Benny Sudakov},
  journal={Eur. J. Comb.},
A subgraph of an edge-coloured graph is called rainbow if all its edges have different colours. The problem of finding rainbow subgraphs goes back to the work of Euler on transversals in Latin squares and was extensively studied since then. In this paper we consider two related questions concerning rainbow subgraphs of complete, edge-coloured graphs and digraphs. In the first part, we show that every properly edge-coloured complete directed graph contains a directed rainbow cycle of length $n-O… Expand
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