/// <summary> /// Solves the problem. /// </summary> /// <returns></returns> protected override IRoute DoSolve(IProblem problem) { // generate some random route first. //IRoute route = OsmSharp.Math.TravellingSalesman.Random.RandomSolver.DoSolve( // problem); IRoute route = solver.Solve(problem); // improve the existing solution. double difference; this.Improve(problem, route, out difference); return(route); }
/// <summary> /// Does the actual solving. /// </summary> /// <param name="problem"></param> /// <returns></returns> protected override IRoute DoSolve(IProblem problem) { // convert to a symetric problem if needed. IProblem _problem = problem; if (!_problem.Symmetric) { _problem = Convertor.ConvertToSymmetric(_problem); _was_asym = true; } // create the list of customers. _customers = new List <int>(); for (int customer = 0; customer < _problem.Size; customer++) { _customers.Add(customer); } _sparse_set = SparseSetHelper.CreateNearestNeighourSet(_problem, _customers, _customers.Count / 10); //_sparse_set = SparseSetHelper.CreateNonSparseSet(_problem, _customers); // construct a route from the customers. //FixedSymmetricRoute init_route = new FixedSymmetricRoute(_customers); // construct a random route using best-placement. ArbitraryInsertionSolver bp_solver = new ArbitraryInsertionSolver(); IRoute bp_route = bp_solver.Solve(_problem); FixedSymmetricRoute init_route = new FixedSymmetricRoute(bp_route); double init_route_weight = LinKernighanSolver.Weight(_problem, init_route); RouteFound route = new RouteFound() { Route = init_route, RouteWeight = init_route_weight }; Console.WriteLine("Route {0}:{1}", route.Route.ToString(), route.RouteWeight); // step 2. EdgeSet X = new EdgeSet(); EdgeSet Y = new EdgeSet(); IList <int> untried_t_1 = new List <int>(route.Route); while (untried_t_1.Count > 0) { // select t1. int t_1 = untried_t_1[0]; untried_t_1.RemoveAt(0); // search route with t_1. RouteFound t_1_route = this.AfterSelectt1(_problem, route, X, Y, t_1); // select the better route. if (t_1_route.RouteWeight < route.RouteWeight) { untried_t_1 = new List <int>(route.Route); route = RouteFound.SelectBest(route, t_1_route); X = new EdgeSet(); Y = new EdgeSet(); } } // step 2 and step 12. // convert back to asym solution if needed. //result.RemoveAt(result.Count - 1); if (_was_asym) { return(this.ConvertToASymRoute(new List <int>(route.Route))); } return(route.Route); }