Fairness - balance number of locations serviced per vehicle

We want to be able to balance the number of locations serviced by each vehicle to be as even as possible. The use-case is for example drivers who are getting paid (at least partially) by number of deliveries.

This constraint should be behind a flag and optional.

Implementation: use the underlying solver to

• Establish a vehicle vars <-> vehicle counts relationship via the Distribute constraint
• Add a Deviation constraint for vehicle counts targeting the deviation var
• Minimizing the deviation var

Roughly as follows:

std::vector<IntVar*> vehicleCounts;

for (auto vehicle = 0; vehicle < numVehicles; ++vehicle)
  vehicleCounts.push_back(solver->MakeIntVar(0, numNodes));

solver->AddConstraint(solver->MakeDistribute(vehicleVars, vehicleCounts));

auto* deviationVar = solver->MakeIntVar(0, numNodes * numNodes);

solver->AddConstraint(solver->MakeDeviation(vehicleCounts, deviationVar, numNodes));

model.AddVariableMinimizedByFinalizer(deviationVar);

Aucun fichier ni test n’est nommé. Commencez par localiser le modèle d’itinéraires de véhicules et sa configuration des contraintes optionnelles, puis examinez comment le solver sous-jacent expose Distribute, Deviation et la minimisation par finalizer. C’est terminé lorsqu’un flag optionnel active un nombre équilibré de lieux par véhicule et que le solver en minimise l’écart.