static void Main(string[] args)
{
Console.Clear();
Console.WriteLine("=========================================================================");
Console.WriteLine("Capacitated Vehicle Routing Problem (CVRP) with GRASP \n Mateus Riad (228157) \n Ricardo Pires (208784) \n");
Console.WriteLine("(All the instances can be found inside this project, dir: instances) \n");
Console.WriteLine("=========================================================================");
Console.WriteLine("Name of the instance to execute: ");
string fileName = Console.ReadLine();
// Pega as informaçoes do arquivo de instancia passado
Parser.parserFile(fileName);
Console.WriteLine("=== EXECUTING GRASP ===\n");
// Inicializa timer
Stopwatch stopWatch = new Stopwatch();
stopWatch.Start();
// GRASP
VCRPInstance instance = new VCRPInstance();
VCRPSolution bestSolution = Grasp.Execute(instance);
stopWatch.Stop();
Console.WriteLine("=== SOLUTION FOUND ===\n");
Console.WriteLine("Best solution found: " + bestSolution.cost);
Console.WriteLine("Executiond Time:" + stopWatch.Elapsed + " seconds.");
for (int k = 0; k < VCRPInstance.n_vehicles; k++)
{
Console.Write("Rota " + k + ":");
List <int> range = bestSolution.routes[k];
foreach (int value in range)
{
Console.Write(value + " - ");
}
Console.WriteLine("\n");
}
string wait = Console.ReadLine();
}
public static VCRPSolution Execute(VCRPInstance instance)
{
/*
* procedure GRASP(Max Iterations,Seed)
* 1 Read Input();
* 2 for k = 1, . . . , Max Iterations do
* 3 Solution ← Greedy Randomized Construction(Seed);
* 4 Solution ← Local Search(Solution);
* 5 Update Solution(Solution,Best Solution);
* 6 end;
* 7 return Best Solution;
* end GRASP.
*/
// Grasp Parameters
int maxIterations = 200;
double alpha = 1;
int seed = 0; // ?
// Initialize best solution with worst cost
const int worstSolution = UInt16.MaxValue;
VCRPSolution bestSolution = new VCRPSolution(VCRPInstance.n_vehicles, VCRPInstance.n_nodes);
bestSolution.cost = worstSolution;
// Solution instance used for grasp iterations
VCRPSolution currentSolution;
for (int k = 0; k < maxIterations; k++)
{
// Constructive Heuristic Phase
currentSolution = GreedyRandomizedSolution(alpha, seed);
Console.WriteLine("=============================================\n");
Console.WriteLine("GREEDY - INITIAL SOLUTION\n");
for (int v = 0; v < VCRPInstance.n_vehicles; v++)
{
Console.Write("Rota " + v + ": ");
List <int> range = currentSolution.routes[v];
foreach (int value in range)
{
Console.Write(value + " - ");
}
Console.WriteLine("\n");
}
Console.WriteLine("Custo total: " + currentSolution.cost + "\n");
// Check and repair solution in case it's not feasible (YET!)
GreedyPostProcessing(currentSolution);
Console.WriteLine("=============================================\n");
Console.WriteLine("GREEDY - POST PROCESSING\n");
for (int v = 0; v < VCRPInstance.n_vehicles; v++)
{
Console.Write("Rota " + v + ":");
List <int> range = currentSolution.routes[v];
foreach (int value in range)
{
Console.Write(value + " - ");
}
Console.WriteLine(getRouteDemand(currentSolution.routes[v]));
Console.WriteLine("\n");
}
Console.WriteLine("Custo total: " + currentSolution.cost + "\n");
// Local Search
//LocalSearch(currentSolution);
/*
* Console.WriteLine("=============================================\n");
* Console.WriteLine("AFTER LOCAL SEARCH\n");
* for (int v = 0; v < VCRPInstance.n_vehicles; v++)
* {
* Console.Write("Rota " + v + ": ");
* List<int> range = currentSolution.routes[v];
* foreach (int value in range)
* {
* Console.Write(value + " - ");
* }
* Console.WriteLine("\n");
* }*/
// Check and update best solution
updateBestSolution(bestSolution, currentSolution);
}
return(bestSolution);
}
