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arXiv · 1609.07450

Finding long simple paths in a weighted digraph using pseudo-topological orderings

Miguel Raggi
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Abstract

Given a weighted digraph D, finding the longest simple path is well known to be NP-hard. Furthermore, even giving an approximation algorithm is known to be NP-hard. In this paper we describe an efficient heuristic algorithm for finding long simple paths, using an hybrid approach of DFS and pseudo-topological orders, a a generalization of topological orders to non acyclic graphs, via a process we call "opening edges". An implementation of this algorithm won the Oracle MDC 2015 coding competition.

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Miguel Raggi. 2016-09-23. Finding long simple paths in a weighted digraph using pseudo-topological orderings. https://arxiv.org/abs/1609.07450

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