SHARC: Fast and Robust Unidirectional Routing

  • Reinhard Bauer ,
  • Daniel Delling

ACM Journal of Experimental Algorithmics | , Vol 14: pp. 2.4-2.29

Special Section on Selected Papers from ALENEX 2008.

During recent years, impressive speed-up techniques for Dijkstra’s have been developed. Unfortunately, the most advanced techniques use bidirectional search, which makes it hard to use them in scenarios where a backward search is prohibited. Even worse, such scenarios are widely spread (e.g., timetable-information systems or time-dependent networks).

In this work, we present a unidirectional speed-up technique, which competes with bidirectional approaches. Moreover, we show how to exploit the advantage of unidirectional routing for fast exact queries in timetable information systems and for fast approximative queries in time-dependent scenarios. By running experiments on several inputs other than road networks, we show that our approach is very robust to the input.