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Defintion

The Open Vehicle Routing Problem (OVRP) is a version of the well known Capacitated Vehicle Routing Problem (CVRP), in which each route ends at the last served customer. More precisely, a vehicle does not return to the depot after servicing the last customer as is the case of the classic CVRP.

This problem can be modeled on a directed graph *G(V,A)*, where each node in* V* represents a customer, 0 means the depot location and arcs in *A* represent connections between them. Each arc *(i, j)* has an associated nonnegative cost *c*_{ij} and each customers *i* has a demand *d*_{i} and a related service time *s*. Furthermore, each vehicle has load capacity limit *Q* and operation time limit *L*.

Each route performed by a vehicle is a Hamiltonian path. Thus each vehicle processes the service demands of its customers using a sequence of adjacent arcs and nodes of the directed graph.

The objective is considering the vehicles' constraints finding a set of valid routes with minimal overall costs.

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Example

The figure below shows the sturcture of the routes in the solution of a OVRP instance

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Instances

A set of OVRP instances is available for testing algorithms.

File format and instances files are available in the file IntancesOVRP_WebOR.zip