Abstract: Traditional route planning algorithms, which mainly focus on metrics such as the distance, time, cost, etc. to find the optimal route from source to destination, are not suitable for solving route planning requirements with location constraints. For example, finding the shortest path passing the whole or a part of user-defined location categories in order or disorder. Mainly focusing on these scenarios, this paper formalizes the constrained route planning problem on the basis of the regular expression generated by user requirements and gives a general framework to solve this problem. Based on this, a basic constrained route planning algorithm (BCRP) and an improved constrained route planning algorithm (ICRP) are proposed while ICRP reduces the search space using pruning rules. Finally, extensive experiments on real road network datasets demonstrate the efficiency of our proposal.

Key words: constrained route planning, the regular expression, the shortest path