Space and time trade-off for the k shortest simple paths problem - Archive ouverte HAL Access content directly
Reports (Research Report) Year : 2020

Space and time trade-off for the k shortest simple paths problem


The k shortest simple path problem (KSSP) asks to compute a set of top-k shortest simple paths from a vertex s to a vertex t in a digraph. Yen (1971) proposed the first algorithm with the best known theoretical complexity of O(kn(m + n log n)) for a digraph with n vertices and m arcs. Since then, the problem has been widely studied from an algorithm engineering perspective, and impressive improvements have been achieved. In particular, Kurz and Mutzel (2016) proposed a sidetracks-based (SB) algorithm which is currently the fastest solution. In this work, we propose two improvements of this algorithm. We first show how to speed up the SB algorithm using dynamic updates of shortest path trees. We did experiments on some road networks of the 9th DIMAC'S challenge with up to about half a million nodes and one million arcs. Our computational results show an average speed up by a factor of 1.5 to 2 with a similar working memory consumption as SB. We then propose a second algorithm enabling to significantly reduce the working memory at the cost of an increase of the running time (up to two times slower). Our experiments on the same data set show, on average, a reduction by a factor of 1.5 to 2 of the working memory.
Fichier principal
Vignette du fichier
HAL_kSSP.pdf (551.41 Ko) Télécharger le fichier
Origin : Files produced by the author(s)

Dates and versions

hal-02465317 , version 1 (03-02-2020)


  • HAL Id : hal-02465317 , version 1


Ali Al Zoobi, David Coudert, Nicolas Nisse. Space and time trade-off for the k shortest simple paths problem. [Research Report] Inria & Université Cote d'Azur, CNRS, I3S, Sophia Antipolis, France. 2020. ⟨hal-02465317⟩
173 View
818 Download


Gmail Facebook X LinkedIn More