/// <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);
}