OR-Tools  8.1
vrp.cc
// Copyright 2010-2018 Google LLC
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// [START program]
// [START import]
#include <vector>
// [END import]
// [START data_model]
struct DataModel {
const std::vector<std::vector<int64>> distance_matrix{
{0, 548, 776, 696, 582, 274, 502, 194, 308, 194, 536, 502, 388, 354, 468,
776, 662},
{548, 0, 684, 308, 194, 502, 730, 354, 696, 742, 1084, 594, 480, 674,
1016, 868, 1210},
{776, 684, 0, 992, 878, 502, 274, 810, 468, 742, 400, 1278, 1164, 1130,
788, 1552, 754},
{696, 308, 992, 0, 114, 650, 878, 502, 844, 890, 1232, 514, 628, 822,
1164, 560, 1358},
{582, 194, 878, 114, 0, 536, 764, 388, 730, 776, 1118, 400, 514, 708,
1050, 674, 1244},
{274, 502, 502, 650, 536, 0, 228, 308, 194, 240, 582, 776, 662, 628, 514,
1050, 708},
{502, 730, 274, 878, 764, 228, 0, 536, 194, 468, 354, 1004, 890, 856, 514,
1278, 480},
{194, 354, 810, 502, 388, 308, 536, 0, 342, 388, 730, 468, 354, 320, 662,
742, 856},
{308, 696, 468, 844, 730, 194, 194, 342, 0, 274, 388, 810, 696, 662, 320,
1084, 514},
{194, 742, 742, 890, 776, 240, 468, 388, 274, 0, 342, 536, 422, 388, 274,
810, 468},
{536, 1084, 400, 1232, 1118, 582, 354, 730, 388, 342, 0, 878, 764, 730,
388, 1152, 354},
{502, 594, 1278, 514, 400, 776, 1004, 468, 810, 536, 878, 0, 114, 308,
650, 274, 844},
{388, 480, 1164, 628, 514, 662, 890, 354, 696, 422, 764, 114, 0, 194, 536,
388, 730},
{354, 674, 1130, 822, 708, 628, 856, 320, 662, 388, 730, 308, 194, 0, 342,
422, 536},
{468, 1016, 788, 1164, 1050, 514, 514, 662, 320, 274, 388, 650, 536, 342,
0, 764, 194},
{776, 868, 1552, 560, 674, 1050, 1278, 742, 1084, 810, 1152, 274, 388,
422, 764, 0, 798},
{662, 1210, 754, 1358, 1244, 708, 480, 856, 514, 468, 354, 844, 730, 536,
194, 798, 0},
};
const int num_vehicles = 4;
};
// [END data_model]
// [START solution_printer]
void PrintSolution(const DataModel& data, const RoutingIndexManager& manager,
const RoutingModel& routing, const Assignment& solution) {
LOG(INFO) << "Objective: " << solution.ObjectiveValue();
int64 total_distance{0};
for (int vehicle_id = 0; vehicle_id < data.num_vehicles; ++vehicle_id) {
int64 index = routing.Start(vehicle_id);
LOG(INFO) << "Route for Vehicle " << vehicle_id << ":";
int64 distance{0};
std::stringstream route;
while (routing.IsEnd(index) == false) {
route << manager.IndexToNode(index).value() << " -> ";
int64 previous_index = index;
index = solution.Value(routing.NextVar(index));
distance += routing.GetArcCostForVehicle(previous_index, index,
int64{vehicle_id});
}
LOG(INFO) << route.str() << manager.IndexToNode(index).value();
LOG(INFO) << "Distance of the route: " << distance << "m";
total_distance += distance;
}
LOG(INFO) << "Total distance of all routes: " << total_distance << "m";
LOG(INFO) << "";
LOG(INFO) << "Advanced usage:";
LOG(INFO) << "Problem solved in " << routing.solver()->wall_time() << "ms";
}
// [END solution_printer]
void Vrp() {
// Instantiate the data problem.
// [START data]
DataModel data;
// [END data]
// Create Routing Index Manager
// [START index_manager]
RoutingIndexManager manager(data.distance_matrix.size(), data.num_vehicles,
data.depot);
// [END index_manager]
// Create Routing Model.
// [START routing_model]
RoutingModel routing(manager);
// [END routing_model]
// Create and register a transit callback.
// [START transit_callback]
const int transit_callback_index = routing.RegisterTransitCallback(
[&data, &manager](int64 from_index, int64 to_index) -> int64 {
// Convert from routing variable Index to distance matrix NodeIndex.
auto from_node = manager.IndexToNode(from_index).value();
auto to_node = manager.IndexToNode(to_index).value();
return data.distance_matrix[from_node][to_node];
});
// [END transit_callback]
// Define cost of each arc.
// [START arc_cost]
routing.SetArcCostEvaluatorOfAllVehicles(transit_callback_index);
// [END arc_cost]
// Setting first solution heuristic.
// [START parameters]
RoutingSearchParameters searchParameters = DefaultRoutingSearchParameters();
searchParameters.set_first_solution_strategy(
FirstSolutionStrategy::PATH_CHEAPEST_ARC);
// [END parameters]
// Solve the problem.
// [START solve]
const Assignment* solution = routing.SolveWithParameters(searchParameters);
// [END solve]
// Print solution on console.
// [START print_solution]
PrintSolution(data, manager, routing, *solution);
// [END print_solution]
}
} // namespace operations_research
int main(int argc, char** argv) {
operations_research::Vrp();
return EXIT_SUCCESS;
}
// [END program]
INFO
const int INFO
Definition: log_severity.h:31
main
int main(int argc, char **argv)
Definition: fz.cc:165
LOG
#define LOG(severity)
Definition: base/logging.h:420
routing.h
value
int64 value
Definition: demon_profiler.cc:43
operations_research
The vehicle routing library lets one model and solve generic vehicle routing problems ranging from th...
Definition: dense_doubly_linked_list.h:21
int64
int64_t int64
Definition: integral_types.h:34
routing_enums.pb.h
operations_research::DefaultRoutingSearchParameters
RoutingSearchParameters DefaultRoutingSearchParameters()
Definition: routing_parameters.cc:44
index
int index
Definition: pack.cc:508
operations_research::RoutingIndexManager::NodeIndex
RoutingNodeIndex NodeIndex
Definition: routing_index_manager.h:50
routing_parameters.h
routing_index_manager.h