Towards a Microscopic Traffic Simulation of All of Switzerland
ICCS '02 Proceedings of the International Conference on Computational Science-Part I
Using Multi-level Graphs for Timetable Information in Railway Systems
ALENEX '02 Revised Papers from the 4th International Workshop on Algorithm Engineering and Experiments
ESA '02 Proceedings of the 10th Annual European Symposium on Algorithms
Structural and algorithmic aspects of massive social networks
SODA '04 Proceedings of the fifteenth annual ACM-SIAM symposium on Discrete algorithms
Information and Computation
Geometric containers for efficient shortest-path computation
Journal of Experimental Algorithmics (JEA)
Combining speed-up techniques for shortest-path computations
Journal of Experimental Algorithmics (JEA)
Language constrained graph problems: a microcosm of engineering research and development
CEA'08 Proceedings of the 2nd WSEAS International Conference on Computer Engineering and Applications
Write it recursively: a generic framework for optimal path queries
Proceedings of the 13th ACM SIGPLAN international conference on Functional programming
Engineering Label-Constrained Shortest-Path Algorithms
AAIM '08 Proceedings of the 4th international conference on Algorithmic Aspects in Information and Management
Information and Computation
Complexity results on labeled shortest path problems from wireless routing metrics
Computer Networks: The International Journal of Computer and Telecommunications Networking
Expressive languages for path queries over graph-structured data
Proceedings of the twenty-ninth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
Algorithm engineering: bridging the gap between algorithm theory and practice
Algorithm engineering: bridging the gap between algorithm theory and practice
Graph indexing of road networks for shortest path queries with label restrictions
Proceedings of the VLDB Endowment
Quickest path distances on context-free labeled graphs
ISP'07 Proceedings of the 6th WSEAS international conference on Information security and privacy
Constrained de novo sequencing of peptides with application to conotoxins
RECOMB'11 Proceedings of the 15th Annual international conference on Research in computational molecular biology
Nodes connected by path languages
DLT'11 Proceedings of the 15th international conference on Developments in language theory
Formal language constrained reachability and model checking propositional dynamic logics
RP'11 Proceedings of the 5th international conference on Reachability problems
Cyclic pattern kernels revisited
PAKDD'05 Proceedings of the 9th Pacific-Asia conference on Advances in Knowledge Discovery and Data Mining
Cuts and disjoint paths in the valley-free path model of internet BGP routing
CAAN'04 Proceedings of the First international conference on Combinatorial and Algorithmic Aspects of Networking
Robustness of the internet at the topology and routing level
Dependable Systems
Query languages for graph databases
ACM SIGMOD Record
A label correcting algorithm for the shortest path problem on a multi-modal route network
SEA'12 Proceedings of the 11th international conference on Experimental Algorithms
Expressive Languages for Path Queries over Graph-Structured Data
ACM Transactions on Database Systems (TODS)
Proceedings of the 32nd symposium on Principles of database systems
A trichotomy for regular simple path queries on graphs
Proceedings of the 32nd symposium on Principles of database systems
Toward general diagnosis of static errors
Proceedings of the 41st ACM SIGPLAN-SIGACT Symposium on Principles of Programming Languages
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Given an alphabet $\Sigma$, a (directed) graph G whose edges are weighted and $\Sigma$-labeled, and a formal language $L\subseteq\Sigma^*$, the formal-language-constrained shortest/simple path problem consists of finding a shortest (simple) path p in G complying with the additional constraint that l(p) \in L$. Here l(p) denotes the unique word obtained by concatenating the $\Sigma$-labels of the edges along the path p. The main contributions of this paper include the following: We show that the formal-language-constrained shortest path problem is solvable efficiently in polynomial time when L is restricted to be a context-free language (CFL). When L is specified as a regular language we provide algorithms with improved space and time bounds. In contrast, we show that the problem of finding a simple path between a source and a given destination is NP-hard, even when L is restricted to fixed simple regular languages and to very simple classes of graphs (e.g., complete grids). For the class of treewidth-bounded graphs, we show that (i) the problem of finding a regular-language-constrained simple path between source and destination is solvable in polynomial time and (ii) the extension to finding CFL-constrained simple paths is NP-complete. Our results extend the previous results in [SIAM J. Comput., 24 (1995), pp. 1235--1258; Proceedings of the 76th Annual Meeting of the Transportation Research Board, 1997; and Proceedings of the 9th ACM SIGACT-SIGMOD-SIGART Symposium on Database Systems, 1990, pp. 230--242]. Several additional extensions and applications of our results in the context of transportation problems are presented. For instance, as a corollary of our results, we obtain a polynomial-time algorithm for the best k-similar path problem studied in Proceedings of the 76th Annual Meeting of the Transportation Reasearch Board, 1997]. The previous best algorithm was given by [ Proceedings of the 76th Annual Meeting of the Transportation Research Board, 1997] and takes exponential time in the worst case.