/// <summary>
/// Test removing adding every customer at every position.
/// </summary>
public void DoTestAddRemoveComplete()
{
// create a new empty route.
const int count = 10;
for (int customerToRemove = 0; customerToRemove < count; customerToRemove++)
{
for (int customerToPlaceAfter = 0; customerToPlaceAfter < count; customerToPlaceAfter++)
{
if (customerToRemove != customerToPlaceAfter)
{
IRoute route = this.BuildRoute(true);
if (route != null)
{ // this part needs testing.
for (int customer = 0; customer < count; customer++)
{
route.InsertAfter(customer - 1, customer);
//route.InsertAfterAndRemove(customer - 1, customer, -1);
}
route.Remove(customerToRemove);
route.InsertAfter(customerToPlaceAfter, customerToRemove);
//route.InsertAfterAndRemove(customer_to_place_after, customer_to_remove, -1);
Assert.IsTrue(route.Contains(customerToPlaceAfter, customerToRemove));
Assert.AreEqual(count, route.Count);
var customersInRoute = new HashSet <int>(route);
Assert.AreEqual(customersInRoute.Count, route.Count);
}
}
}
}
}
/// <summary>
/// Tests all enumerations of a route.
/// </summary>
protected void DoTestEnumerateBetween()
{
int count = 10;
IRoute route = this.BuildRoute(true);
if (route != null)
{ // this part needs testing.
for (int customer = 0; customer < count; customer++)
{
route.InsertAfter(customer - 1, customer);
//route.InsertAfterAndRemove(customer - 1, customer, -1);
}
}
for (int from = 0; from < count; from++)
{
for (int to = 0; to < count; to++)
{
IEnumerator <int> enumerator = route.Between(from, to).GetEnumerator();
for (int customer = from; customer - 1 != to; customer++)
{
if (customer == count)
{
customer = 0;
}
Assert.IsTrue(enumerator.MoveNext());
Assert.AreEqual(customer, enumerator.Current);
}
}
}
}
/// <summary>
/// Tests enumeration all edges.
/// </summary>
protected void DoTestEnumeratePairs()
{
// create a new empty route.
IRoute route = this.BuildRoute(0, true);
// do the enumerable.
List <Edge> edges = new List <Edge>(route.Edges());
Assert.AreEqual(0, edges.Count);
if (route != null)
{ // this part needs testing!
Assert.AreEqual(1, route.Count);
Assert.AreEqual(false, route.IsEmpty);
Assert.AreEqual(true, route.IsRound);
for (int customer = 1; customer < 100; customer++)
{
route.InsertAfter(customer - 1, customer);
//route.InsertAfterAndRemove(customer - 1, customer, -1);
edges = new List <Edge>(route.Edges());
Assert.AreEqual(customer + 1, edges.Count);
for (int edge_from = 0; edge_from < customer; edge_from++)
{
Assert.AreEqual(edges[edge_from].From, edge_from);
Assert.AreEqual(edges[edge_from].To, edge_from + 1);
}
Assert.AreEqual(edges[edges.Count - 1].From, edges.Count - 1);
Assert.AreEqual(edges[edges.Count - 1].To, 0);
}
}
}
/// <summary>
/// Tests if the route containts functions work correctly.
/// </summary>
public void DoTestContains()
{
// create a new empty route.
const int count = 100;
IRoute route = this.BuildRoute(true);
if (route != null)
{ // this part needs testing.
Assert.AreEqual(0, route.Count);
Assert.AreEqual(true, route.IsEmpty);
Assert.AreEqual(true, route.IsRound);
for (int customer = 0; customer < count; customer++)
{
route.InsertAfter(customer - 1, customer);
//route.InsertAfterAndRemove(customer - 1, customer, -1);
Assert.AreEqual(customer + 1, route.Count);
Assert.AreEqual(false, route.IsEmpty);
Assert.AreEqual(true, route.IsRound);
Assert.AreEqual(0, route.First);
Assert.AreEqual(0, route.Last);
}
for (int customer = 0; customer < count - 1; customer++)
{
Assert.IsTrue(route.Contains(customer));
Assert.IsTrue(route.Contains(customer, customer + 1));
}
Assert.IsTrue(route.Contains(count - 1));
Assert.IsTrue(route.Contains(count - 1, 0));
}
}
/// <summary>
/// Some tests on an IRoute.
/// </summary>
public void DoTestAdd()
{
// create a new empty route.
IRoute route = this.BuildRoute(0, true);
if (route != null)
{ // this part needs testing!
Assert.AreEqual(1, route.Count);
Assert.AreEqual(false, route.IsEmpty);
Assert.AreEqual(true, route.IsRound);
for (int customer = 1; customer < 100; customer++)
{
route.InsertAfter(customer - 1, customer);
//route.InsertAfterAndRemove(customer - 1, customer, -1);
Assert.AreEqual(customer + 1, route.Count);
Assert.AreEqual(false, route.IsEmpty);
Assert.AreEqual(true, route.IsRound);
Assert.AreEqual(0, route.First);
Assert.AreEqual(0, route.Last);
}
}
// create a new empty route.
route = this.BuildRoute(true);
if (route != null)
{ // this part needs testing.
Assert.AreEqual(0, route.Count);
Assert.AreEqual(true, route.IsEmpty);
Assert.AreEqual(true, route.IsRound);
for (int customer = 0; customer < 100; customer++)
{
route.InsertAfter(customer - 1, customer);
//route.InsertAfterAndRemove(customer - 1, customer, -1);
Assert.AreEqual(customer + 1, route.Count);
Assert.AreEqual(false, route.IsEmpty);
Assert.AreEqual(true, route.IsRound);
Assert.AreEqual(0, route.First);
Assert.AreEqual(0, route.Last);
}
}
}
/// <summary>
/// Removes the edge from->unknown and replaces it with the edge from->to->unknown.
/// 0->1:InsertAfter(0, 2):0->2-1
/// </summary>
/// <param name="from"></param>
/// <param name="to"></param>
public void InsertAfter(int from, int to)
{
if (from == 0)
{
_route.InsertFirst(to);
}
else
{
_route.InsertAfter(from, to);
}
}
/// <summary>
/// Generates individuals based on a random first customer for each route.
/// </summary>
/// <param name="solver"></param>
/// <returns></returns>
public Individual <MaxTimeSolution, MaxTimeProblem, Fitness> Generate(
Solver <MaxTimeSolution, MaxTimeProblem, Fitness> solver)
{
MaxTimeProblem problem = solver.Problem;
MaxTimeSolution solution = new MaxTimeSolution(problem.Size, true);
// create the problem for the genetic algorithm.
List <int> customers = new List <int>();
for (int customer = 0; customer < problem.Size; customer++)
{
customers.Add(customer);
}
//BestPlacementHelper helper = new BestPlacementHelper();
// keep placing customer until none are left.
while (customers.Count > 0)
{
// select a random customer.
double weight = 0;
int customer_idx = OsmSharp.Math.Random.StaticRandomGenerator.Get().Generate(customers.Count);
int customer = customers[customer_idx];
customers.RemoveAt(customer_idx);
// use best placement to generate a route.
IRoute current_route = solution.Add(customer);
//Console.WriteLine("Starting new route with {0}", customer);
while (customers.Count > 0)
{
// calculate the best placement.
int customer_to_place = customers[OsmSharp.Math.Random.StaticRandomGenerator.Get().Generate(customers.Count)];
CheapestInsertionResult result = CheapestInsertionHelper.CalculateBestPlacement(problem, current_route, customer_to_place);
// calculate the new weight.
double potential_weight = result.Increase + weight + 20;
// cram as many customers into one route as possible.
if (potential_weight < problem.Max.Value)
{ // ok we are done!
customers.Remove(result.Customer);
//current_route.InsertAfterAndRemove(result.CustomerBefore, result.Customer, result.CustomerAfter);
current_route.InsertAfter(result.CustomerBefore, result.Customer);
weight = potential_weight;
}
else
{
break;
}
}
}
return(new Individual <MaxTimeSolution, MaxTimeProblem, Fitness>(solution));
}
/// <summary>
/// Tests adding customers.
/// </summary>
public void DoTestRemove()
{
IMultiRoute multiRoute = this.BuildRoute(true);
Assert.AreEqual(0, multiRoute.Count);
int count = 10;
int routes = 3;
// test with initializing the routes empty.
var customersPerRoute = new List <List <int> >();
Assert.AreEqual(0, multiRoute.Count);
for (int routeIdx = 0; routeIdx < routes; routeIdx++)
{
customersPerRoute.Add(new List <int>());
int customerStart = (routeIdx * count);
IRoute route = multiRoute.Add();
for (int customer = customerStart; customer < customerStart + count; customer++)
{
customersPerRoute[routeIdx].Add(customer);
route.InsertAfter(customer - 1, customer);
//route.InsertAfterAndRemove(customer - 1, customer, -1);
}
}
// remove all the customers.
while (customersPerRoute.Count > 0)
{
int routeIdx = OsmSharp.Math.Random.StaticRandomGenerator.Get().Generate(customersPerRoute.Count);
int customerIdx = OsmSharp.Math.Random.StaticRandomGenerator.Get().Generate(customersPerRoute[routeIdx].Count);
int customer = customersPerRoute[routeIdx][customerIdx];
customersPerRoute[routeIdx].RemoveAt(customerIdx);
IRoute route = multiRoute.Route(routeIdx);
route.Remove(customer);
Assert.AreEqual(customersPerRoute[routeIdx].Count, route.Count);
Assert.AreEqual(customersPerRoute[routeIdx].Count == 0, route.IsEmpty);
Assert.AreEqual(true, route.IsRound);
Assert.AreEqual(route.First, route.Last);
if (customersPerRoute[routeIdx].Count == 0)
{
customersPerRoute.RemoveAt(routeIdx);
multiRoute.Remove(routeIdx);
}
}
}
/// <summary>
/// Re-inserts a customer in the route.
/// </summary>
/// <param name="weights"></param>
/// <param name="route"></param>
/// <param name="customer"></param>
/// <param name="difference"></param>
/// <returns></returns>
public static bool InsertOne(IProblemWeights weights, IRoute route, int customer,
out double difference)
{
// calculate placement.
CheapestInsertionResult result =
CheapestInsertionHelper.CalculateBestPlacement(weights, route, customer);
// place the customer.
if (result.CustomerAfter >= 0 && result.CustomerBefore >= 0)
{
//route.InsertAfterAndRemove(result.CustomerBefore, result.Customer, result.CustomerAfter);
route.InsertAfter(result.CustomerBefore, result.Customer);
difference =
-(weights.WeightMatrix[result.CustomerBefore][result.CustomerAfter]) +
(weights.WeightMatrix[result.CustomerBefore][result.Customer]) +
(weights.WeightMatrix[result.Customer][result.CustomerAfter]);
return(true);
}
difference = 0;
return(false);
}
/// <summary>
/// Do get neighbour tests.
/// </summary>
protected void DoTestGetNeighbours()
{
int count = 10;
IRoute route = this.BuildRoute(true);
if (route != null)
{ // this part needs testing.
for (int customer = 0; customer < count; customer++)
{
route.InsertAfter(customer - 1, customer);
//route.InsertAfterAndRemove(customer - 1, customer, -1);
}
}
int[] neighbours;
for (int customer = 0; customer < count - 1; customer++)
{
neighbours = route.GetNeigbours(customer);
Assert.IsTrue(neighbours[0] == customer + 1);
}
neighbours = route.GetNeigbours(count - 1);
Assert.IsTrue(neighbours[0] == 0);
}
public MaxTimeSolution ChangeSizes(MaxTimeProblem problem, MaxTimeSolution solution, IEnumerable <int> sizes)
{
MaxTimeSolution changed_solution = new MaxTimeSolution(
solution.Size, true);
//int[] next_array = new int[solution.Size];
bool[] used = new bool[solution.Size];
//List<int> first = new List<int>();
foreach (int size in sizes)
{
int current = 0;
while (used[current])
{
current++;
}
IRoute route = changed_solution.Add(current);
used[current] = true;
int current_size = size - 1;
int previous = current;
while (current_size > 0)
{
// choose the next customer.
current = solution.Next(current);
if (used[current])
{
double neighbour_weight = double.MaxValue;
foreach (int nn in problem.Get10NearestNeighbours(previous))
{
if (!used[nn])
{
double potential_weight =
problem.WeightMatrix[previous][current];
if (potential_weight < neighbour_weight)
{
current = nn;
neighbour_weight = potential_weight;
}
//break;
}
}
int used_count = 0;
while (used[current])
{
current++;
used_count++;
if (current == solution.Size)
{
current = 0;
}
//if (used_count == problem.Size)
//{
// break;
//}
}
}
// set the next array.
//route.InsertAfterAndRemove(previous, current, route.First);
route.InsertAfter(previous, current);
used[current] = true;
previous = current;
current_size--;
}
if (!changed_solution.IsValid())
{
throw new Exception();
}
}
return(changed_solution);
}
/// <summary>
/// Executes a solver procedure.
/// </summary>
/// <param name="problem"></param>
/// <returns></returns>
internal override MaxTimeSolution Solve(MaxTimeProblem problem)
{
// create the solution.
var solution = new MaxTimeSolution(problem.Size);
// keep placing customer until none are left.
var customers = new List <int>(problem.Customers);
customers.RemoveAt(0);
double max = problem.Max.Value - (problem.Max.Value * _deltaPercentage);
// keep a list of cheapest insertions.
IInsertionCosts costs = new BinaryHeapInsertionCosts();
double percentage = _thresholdPercentage;
while (customers.Count > 0)
{
//// try and distribute the remaining customers if there are only a few left.
//if (customers.Count < problem.Size * percentage)
//{
// bool succes = true;
// while (succes && customers.Count > 0)
// {
// succes = false;
// CheapestInsertionResult best = new CheapestInsertionResult();
// best.Increase = float.MaxValue;
// int best_idx = -1;
// for (int route_idx = 0; route_idx < solution.Count; route_idx++)
// {
// IRoute route = solution.Route(route_idx);
// CheapestInsertionResult result =
// CheapestInsertionHelper.CalculateBestPlacement(problem, route, customers);
// if (best.Increase > result.Increase)
// {
// best = result;
// best_idx = route_idx;
// }
// }
// IRoute best_route = solution.Route(best_idx);
// double route_time = problem.Time(best_route);
// if (route_time + best.Increase < max)
// { // insert the customer.
// best_route.InsertAfter(best.CustomerBefore, best.Customer);
// customers.Remove(best.Customer);
// this.Improve(problem, solution, max, best_idx);
// succes = true;
// }
// }
//}
// select a customer using some heuristic.
int customer = this.SelectSeed(problem, problem.MaxTimeCalculator, solution, customers);
customers.Remove(customer);
// start a route r.
IRoute currentRoute = solution.Add(customer);
solution[solution.Count - 1] = 0;
while (customers.Count > 0)
{
// calculate the best placement.
CheapestInsertionResult result;
if (_useSeedCost)
{ // use the seed cost; the cost to the seed customer.
result = CheapestInsertionHelper.CalculateBestPlacement(problem, currentRoute, customers,
customer, 0.7);
// calculate the 'real' increase.
result.Increase = (problem.WeightMatrix[result.CustomerBefore][result.Customer] +
problem.WeightMatrix[result.Customer][result.CustomerAfter]) -
problem.WeightMatrix[result.CustomerBefore][result.CustomerAfter];
}
else
{ // just use cheapest insertion.
result = CheapestInsertionHelper.CalculateBestPlacement(problem, currentRoute, customers, costs);
}
// calculate the new weight.
solution[solution.Count - 1] = problem.Time(solution.Route(solution.Count - 1));
double potentialWeight = problem.MaxTimeCalculator.CalculateOneRouteIncrease(solution[solution.Count - 1],
result.Increase);
// cram as many customers into one route as possible.
if (potentialWeight < max)
{
// insert the customer, it is
customers.Remove(result.Customer);
currentRoute.InsertAfter(result.CustomerBefore, result.Customer);
// free some memory in the costs list.
costs.Remove(result.CustomerBefore, result.CustomerAfter);
// update the cost of the route.
solution[solution.Count - 1] = potentialWeight;
// improve if needed.
if (((problem.Size - customers.Count) % _k) == 0)
{ // an improvement is decided.
// apply the inter-route improvements.
var copy = (solution.Clone() as MaxTimeSolution);
int countBefore = solution.Route(solution.Count - 1).Count;
solution[solution.Count - 1] = this.ImproveIntraRoute(problem,
solution.Route(solution.Count - 1), solution[solution.Count - 1]);
if (!solution.IsValid())
{
throw new Exception();
}
int countAfter = solution.Route(solution.Count - 1).Count;
if (countAfter != countBefore)
{
throw new Exception();
}
// also to the inter-improvements.
currentRoute = this.Improve(problem, solution, max, solution.Count - 1);
}
}
else
{// ok we are done!
this.Improve(problem, solution, max, solution.Count - 1);
// break the route.
break;
}
}
}
// remove empty routes.
for (int routeIdx = solution.Count - 1; routeIdx >= 0; routeIdx--)
{
if (solution.Route(routeIdx).IsEmpty)
{
solution.Remove(routeIdx);
}
}
return(solution);
}
/// <summary>
/// Applies a local search strategy.
/// </summary>
/// <param name="problem"></param>
/// <param name="route"></param>
/// <returns></returns>
public static void CalculateRePlaceOptHelper(
IProblemWeights problem, IRoute route)
{
//bool improvement = true;
//while (improvement)
//{
//// reset improvement flag.
//improvement = false;
// try re-placement of one customer.
int before = -1;
//int after = -1;
int found_customer = -1;
// loop over all customers and try to place it better.
HashSet <int> customers_to_place = new HashSet <int>(route);
foreach (int customer_to_place in customers_to_place)
{
// find the best place.
double current_cost = -1;
double other_cost = double.MaxValue;
int previous_before = -1;
int previous = -1;
foreach (int customer in route)
{
if (previous >= 0 && previous_before >= 0)
{
if (previous == customer_to_place)
{
current_cost = problem.Weight(previous_before, previous) +
problem.Weight(previous, customer);
}
else if (previous_before != customer_to_place &&
customer != customer_to_place)
{ // calculate the cost.
double cost = problem.Weight(previous_before, customer_to_place) +
problem.Weight(customer_to_place, previous);
if (cost < other_cost)
{
other_cost = cost;
before = previous_before;
//after = previous;
found_customer = customer;
}
}
}
previous_before = previous;
previous = customer;
}
// determine if the cost is better.
if (current_cost > other_cost)
{ // the current cost is better.
route.Remove(found_customer);
//route.InsertAfterAndRemove(before, found_customer, after);
route.InsertAfter(before, found_customer);
break;
}
else
{ // current cost is not better.
before = -1;
//after = -1;
found_customer = -1;
}
}
//if (found_customer >= 0)
//{ // a found customer.
// improvement = true;
//}
//}
}
/// <summary>
/// Generates individuals based on a random first customer for each route.
/// </summary>
/// <param name="solver"></param>
/// <returns></returns>
public Individual <List <Genome>, Problem, Fitness> Generate(
Solver <List <Genome>, Problem, Fitness> solver)
{
Problem problem = solver.Problem;
DynamicAsymmetricMultiRoute multi_route = new DynamicAsymmetricMultiRoute(problem.Size, true);
// create the problem for the genetic algorithm.
List <int> customers = new List <int>();
for (int customer = problem.Depots.Count; customer < problem.Size; customer++)
{
customers.Add(customer);
}
CheapestInsertionHelper helper = new CheapestInsertionHelper();
List <double> weights = new List <double>();
for (int i = 0; i < problem.Depots.Count; i++)
{
multi_route.Add(i);
weights.Add(0);
}
int k = OsmSharp.Math.Random.StaticRandomGenerator.Get().Generate(problem.Depots.Count);
// keep placing customer until none are left.
while (customers.Count > 0)
{
k = (k + 1) % problem.Depots.Count;
// use best placement to generate a route.
IRoute current_route = multi_route.Route(k);
//Console.WriteLine("Starting new route with {0}", customer);
while (customers.Count > 0)
{
// calculate the best placement.
CheapestInsertionResult result = CheapestInsertionHelper.CalculateBestPlacement(problem, current_route, customers);
if (result.CustomerAfter == -1 || result.CustomerBefore == -1)
{
customers.Remove(result.Customer);
continue;
}
// calculate the new weight.
customers.Remove(result.Customer);
//current_route.InsertAfterAndRemove(result.CustomerBefore, result.Customer, result.CustomerAfter);
current_route.InsertAfter(result.CustomerBefore, result.Customer);
weights[k] += result.Increase + 15 * 60;
if (weights[k] == weights.Max())
{
break;
}
}
}
for (int i = 0; i < problem.Depots.Count; i++)
{
multi_route.RemoveCustomer(i);
}
List <Genome> genomes = new List <Genome>();
genomes.Add(Genome.CreateFrom(multi_route));
Individual <List <Genome>, Problem, Fitness> individual = new Individual <List <Genome>, Problem, Fitness>(genomes);
//individual.Initialize();
return(individual);
}
public Individual <MaxTimeSolution, MaxTimeProblem, Fitness> CrossOver(
Solver <MaxTimeSolution, MaxTimeProblem, Fitness> solver,
Individual <MaxTimeSolution, MaxTimeProblem, Fitness> parent1,
Individual <MaxTimeSolution, MaxTimeProblem, Fitness> parent2)
{
MaxTimeCalculator calculator = new MaxTimeCalculator(solver.Problem);
MaxTimeSolution route1 = parent1.Genomes;
MaxTimeSolution route2 = parent2.Genomes;
// get the minimum size of both routes.
int size = route1.Count;
if (route2.Count < size)
{
size = route2.Count;
}
// select a random number of routes.
HashSet <int> selected_first = new HashSet <int>();
HashSet <int> selected_second = new HashSet <int>();
List <IRoute> selected_routes = new List <IRoute>();
bool first = true;
while (selected_routes.Count < size)
{
// select route.
int selected_route = -1;
if (first)
{
selected_route = this.ChooseNextFrom(selected_routes, route1, selected_first);
selected_first.Add(selected_route);
selected_routes.Add(route1.Route(selected_route));
}
else
{
selected_route = this.ChooseNextFrom(selected_routes, route2, selected_second);
selected_second.Add(selected_route);
selected_routes.Add(route2.Route(selected_route));
}
first = !first;
}
// generate the new customer genome.
MaxTimeSolution solution = new MaxTimeSolution(route1.Size, true);
int previous = -1;
foreach (IRoute route in selected_routes)
{
IRoute current_route = null;
foreach (int customer in route)
{
MaxTimeSolution copy = (solution.Clone() as MaxTimeSolution);
string solution_string = solution.ToString();
if (!solution.Contains(customer))
{
if (current_route == null)
{ // add the route.
current_route = solution.Add(customer);
// safe the previous customer.
previous = customer;
if (!solution.IsValid())
{
throw new Exception();
}
}
else
{ // add the customer.
string current_route_string = current_route.ToString();
//current_route.InsertAfterAndRemove(previous, customer, current_route.First);
current_route.InsertAfter(previous, customer);
//current_route.InsertAfter(customer, current_route.First);
if (!solution.IsValid())
{
throw new Exception();
}
// safe the previous customer.
previous = customer;
}
}
}
}
if (!solution.IsValid())
{
throw new Exception();
}
this.FillRoutes(calculator, route1, solution, solver.Problem);
if (!solution.IsValid())
{
throw new Exception();
}
return(new Individual <MaxTimeSolution, MaxTimeProblem, Fitness>(solution));
}
/// <summary>
/// Applies a local search strategy.
/// </summary>
/// <param name="problem"></param>
/// <param name="route"></param>
/// <returns></returns>
public static void CalculateRePlaceOptHelper(
IProblemWeights problem, IRoute route)
{
//bool improvement = true;
//while (improvement)
//{
//// reset improvement flag.
//improvement = false;
// try re-placement of one customer.
int before = -1;
int after = -1;
int found_customer = -1;
// loop over all customers and try to place it better.
HashSet<int> customers_to_place = new HashSet<int>(route);
foreach (int customer_to_place in customers_to_place)
{
// find the best place.
double current_cost = -1;
double other_cost = double.MaxValue;
int previous_before = -1;
int previous = -1;
foreach (int customer in route)
{
if (previous >= 0 && previous_before >= 0)
{
if (previous == customer_to_place)
{
current_cost = problem.Weight(previous_before, previous) +
problem.Weight(previous, customer);
}
else if (previous_before != customer_to_place &&
customer != customer_to_place)
{ // calculate the cost.
double cost = problem.Weight(previous_before, customer_to_place) +
problem.Weight(customer_to_place, previous);
if (cost < other_cost)
{
other_cost = cost;
before = previous_before;
after = previous;
found_customer = customer;
}
}
}
previous_before = previous;
previous = customer;
}
// determine if the cost is better.
if (current_cost > other_cost)
{ // the current cost is better.
route.Remove(found_customer);
//route.InsertAfterAndRemove(before, found_customer, after);
route.InsertAfter(before, found_customer);
break;
}
else
{ // current cost is not better.
before = -1;
after = -1;
found_customer = -1;
}
}
//if (found_customer >= 0)
//{ // a found customer.
// improvement = true;
//}
//}
}
/// <summary>
/// Executes a solver procedure.
/// </summary>
/// <param name="problem"></param>
/// <returns></returns>
internal override MaxTimeSolution Solve(MaxTimeProblem problem)
{
// create the calculator.
MaxTimeCalculator calculator = new MaxTimeCalculator(problem);
// create the solution.
MaxTimeSolution solution = new MaxTimeSolution(problem.Size, true);
// keep placing customer until none are left.
List <int> customers = new List <int>(problem.Customers);
while (customers.Count > 0)
{
// select a customer using some heuristic.
int customer_idx = OsmSharp.Math.Random.StaticRandomGenerator.Get().Generate(customers.Count);
int customer = customers[customer_idx];
customers.Remove(customer);
// start a route r.
double current_route_weight = 0;
IRoute current_route = solution.Add(customer);
//Console.WriteLine("Starting new route with {0}", customer);
while (customers.Count > 0)
{
// calculate the best placement.
CheapestInsertionResult result =
CheapestInsertionHelper.CalculateBestPlacement(problem, current_route, customers);
// calculate the new weight.
double potential_weight = calculator.CalculateOneRouteIncrease(current_route_weight, result.Increase);
// cram as many customers into one route as possible.
if (potential_weight < problem.Max.Value)
{
// insert the customer, it is
customers.Remove(result.Customer);
//current_route.InsertAfterAndRemove(result.CustomerBefore, result.Customer, result.CustomerAfter);
current_route.InsertAfter(result.CustomerBefore, result.Customer);
current_route_weight = potential_weight;
//// improve if needed.
////if (improvement_probalitity > OsmSharp.Math.Random.StaticRandomGenerator.Get().Generate(1))
//if (((problem.Size - customers.Count) % _k) == 0)
//{ // an improvement is descided.
// current_route_weight = this.ImproveIntraRoute(problem,
// current_route, current_route_weight);
//}
}
else
{// ok we are done!
//// apply the intra-route heuristics.
//for (int route_idx = 0; route_idx < solution.Count - 1; route_idx++)
//{ // apply the intra-route heurstic between the new and all existing routes.
// this.ImproveInterRoute(problem, solution.Route(route_idx), current_route);
//}
//// apply the inter-route heuristics.
//for (int route_idx = 0; route_idx < solution.Count; route_idx++)
//{ // apply heurstic for each route.
// IRoute route = solution.Route(route_idx);
// this.ImproveIntraRoute(problem, current_route, current_route_weight);
//}
// break the route.
break;
}
}
}
return(solution);
}
/// <summary>
/// Executes a solver procedure.
/// </summary>
/// <param name="problem"></param>
/// <returns></returns>
internal override MaxTimeSolution Solve(MaxTimeProblem problem)
{
// create the solution.
MaxTimeSolution solution = new MaxTimeSolution(problem.Size, true);
// keep placing customer until none are left.
List <int> customers = new List <int>(problem.Customers);
double max = problem.Max.Value - (problem.Max.Value * _delta_percentage);
// keep a list of cheapest insertions.
IInsertionCosts costs = new BinaryHeapInsertionCosts();
double percentage = _threshold_percentage;
while (customers.Count > 0)
{
// try and distribute the remaining customers if there are only a few left.
if (customers.Count < problem.Size * percentage)
{
bool succes = true;
while (succes && customers.Count > 0)
{
succes = false;
CheapestInsertionResult best = new CheapestInsertionResult();
best.Increase = float.MaxValue;
int best_idx = -1;
for (int route_idx = 0; route_idx < solution.Count; route_idx++)
{
IRoute route = solution.Route(route_idx);
CheapestInsertionResult result =
CheapestInsertionHelper.CalculateBestPlacement(problem, route, customers);
if (best.Increase > result.Increase)
{
best = result;
best_idx = route_idx;
}
}
IRoute best_route = solution.Route(best_idx);
double route_time = problem.Time(best_route);
if (route_time + best.Increase < max)
{ // insert the customer.
best_route.InsertAfter(best.CustomerBefore, best.Customer);
customers.Remove(best.Customer);
this.Improve(problem, solution, max, best_idx);
succes = true;
}
}
}
// select a customer using some heuristic.
if (customers.Count > 0)
{
// select a customer using some heuristic.
int customer = -1;
if (_use_seed)
{ // use a seeding heuristic.
customer = this.SelectSeed(problem, problem.MaxTimeCalculator, solution, customers);
}
else
{ // just select a random customer.
customer = customers[Math.Random.StaticRandomGenerator.Get().Generate(customers.Count)];
}
customers.Remove(customer);
// start a route r.
IRoute current_route = solution.Add(customer);
solution[solution.Count - 1] = 0;
while (customers.Count > 0)
{
//OsmSharp.IO.Output.OutputStreamHost.WriteLine("{0}/{1} placed!",
// customers.Count, problem.Size);
// calculate the best placement.
CheapestInsertionResult result;
if (_use_seed_cost)
{ // use the seed cost; the cost to the seed customer.
result = CheapestInsertionHelper.CalculateBestPlacement(problem, current_route, customers,
customer, _lambda);
// calculate the 'real' increase.
result.Increase = (problem.WeightMatrix[result.CustomerBefore][result.Customer] +
problem.WeightMatrix[result.Customer][result.CustomerAfter]) -
problem.WeightMatrix[result.CustomerBefore][result.CustomerAfter];
}
else
{ // just use cheapest insertion.
result = CheapestInsertionHelper.CalculateBestPlacement(problem, current_route, customers, costs);
}
// calculate the new weight.
solution[solution.Count - 1] = problem.Time(solution.Route(solution.Count - 1));
double potential_weight = problem.MaxTimeCalculator.CalculateOneRouteIncrease(solution[solution.Count - 1],
result.Increase);
// cram as many customers into one route as possible.
if (potential_weight < max)
{
// insert the customer, it is
customers.Remove(result.Customer);
current_route.InsertAfter(result.CustomerBefore, result.Customer);
// free some memory in the costs list.
costs.Remove(result.CustomerBefore, result.CustomerAfter);
// update the cost of the route.
solution[solution.Count - 1] = potential_weight;
// improve if needed.
if (((problem.Size - customers.Count) % _k) == 0)
{ // an improvement is descided.
// apply the inter-route improvements.
int count_before = solution.Route(solution.Count - 1).Count;
solution[solution.Count - 1] = this.ImproveIntraRoute(problem,
current_route, solution[solution.Count - 1]);
if (!solution.IsValid())
{
throw new Exception();
}
int count_after = solution.Route(solution.Count - 1).Count;
// also to the inter-improvements.
current_route = this.Improve(problem, solution, max, solution.Count - 1);
}
}
else
{// ok we are done!
this.Improve(problem, solution, max, solution.Count - 1);
// break the route.
break;
}
}
//else
//{// ok we are done!
// solution[solution.Count - 1] = this.ImproveIntraRoute(problem,
// current_route, solution[solution.Count - 1]);
// if (!solution.IsValid())
// {
// throw new Exception();
// }
// int count_after = solution.Route(solution.Count - 1).Count;
// this.Improve(problem, solution, max, solution.Count - 1);
// // break the route.
// break;
//}
}
}
// remove empty routes.
for (int route_idx = solution.Count - 1; route_idx >= 0; route_idx--)
{
if (solution.Route(route_idx).IsEmpty)
{
solution.Remove(route_idx);
}
}
return(solution);
}
/// <summary>
/// Tests adding customers.
/// </summary>
public void DoTestAdd()
{
IMultiRoute multiRoute = this.BuildRoute(true);
Assert.AreEqual(0, multiRoute.Count);
int count = 10;
int routes = 3;
for (int routeIdx = 0; routeIdx < routes; routeIdx++)
{
int customerStart = (routeIdx * count);
IRoute route = multiRoute.Add(customerStart);
Assert.AreEqual(1, route.Count);
Assert.AreEqual(false, route.IsEmpty);
Assert.AreEqual(true, route.IsRound);
for (int customer = customerStart + 1; customer < customerStart + count; customer++)
{
route.InsertAfter(customer - 1, customer);
Assert.AreEqual(customer - customerStart + 1, route.Count);
Assert.AreEqual(false, route.IsEmpty);
Assert.AreEqual(true, route.IsRound);
Assert.AreEqual(customerStart, route.First);
Assert.AreEqual(customerStart, route.Last);
}
for (int customer = customerStart + 1; customer < customerStart + count - 1; customer++)
{
Assert.IsTrue(route.Contains(customer));
Assert.IsTrue(route.Contains(customer, customer + 1));
}
Assert.IsTrue(route.Contains(customerStart + count - 1));
Assert.IsTrue(route.Contains(customerStart + count - 1, customerStart));
Assert.AreEqual(routeIdx + 1, multiRoute.Count);
Assert.AreEqual(count * (routeIdx + 1), multiRoute.Size);
}
// test with initializing the routes empty.
multiRoute = this.BuildRoute(true);
Assert.AreEqual(0, multiRoute.Count);
for (int routeIdx = 0; routeIdx < routes; routeIdx++)
{
int customerStart = (routeIdx * count);
IRoute route = multiRoute.Add();
Assert.AreEqual(0, route.Count);
Assert.AreEqual(true, route.IsEmpty);
Assert.AreEqual(true, route.IsRound);
for (int customer = customerStart; customer < customerStart + count; customer++)
{
route.InsertAfter(customer - 1, customer);
Assert.AreEqual(customer - customerStart + 1, route.Count);
Assert.AreEqual(false, route.IsEmpty);
Assert.AreEqual(true, route.IsRound);
Assert.AreEqual(customerStart, route.First);
Assert.AreEqual(customerStart, route.Last);
}
for (int customer = customerStart; customer < customerStart + count - 1; customer++)
{
Assert.IsTrue(route.Contains(customer));
Assert.IsTrue(route.Contains(customer, customer + 1));
}
Assert.IsTrue(route.Contains(customerStart + count - 1));
Assert.IsTrue(route.Contains(customerStart + count - 1, customerStart));
Assert.AreEqual(routeIdx + 1, multiRoute.Count);
Assert.AreEqual(count * (routeIdx + 1), multiRoute.Size);
}
}
/// <summary>
/// Re-inserts a customer in the route.
/// </summary>
/// <param name="weights"></param>
/// <param name="route"></param>
/// <param name="customer"></param>
/// <param name="difference"></param>
/// <returns></returns>
public static bool InsertOne(IProblemWeights weights, IRoute route, int customer,
out double difference)
{
// calculate placement.
CheapestInsertionResult result =
CheapestInsertionHelper.CalculateBestPlacement(weights, route, customer);
// place the customer.
if (result.CustomerAfter >= 0 && result.CustomerBefore >= 0)
{
//route.InsertAfterAndRemove(result.CustomerBefore, result.Customer, result.CustomerAfter);
route.InsertAfter(result.CustomerBefore, result.Customer);
difference =
-(weights.WeightMatrix[result.CustomerBefore][result.CustomerAfter]) +
(weights.WeightMatrix[result.CustomerBefore][result.Customer]) +
(weights.WeightMatrix[result.Customer][result.CustomerAfter]);
return true;
}
difference = 0;
return false;
}
/// <summary>
/// Does the mutation.
/// </summary>
/// <param name="solver"></param>
/// <param name="mutating"></param>
/// <returns></returns>
public Individual <MaxTimeSolution, MaxTimeProblem, Fitness> Mutate(
Solver <MaxTimeSolution, MaxTimeProblem, Fitness> solver,
Individual <MaxTimeSolution, MaxTimeProblem, Fitness> mutating)
{
// get the route information.
MaxTimeSolution multi_route = mutating.Genomes.Clone() as MaxTimeSolution;
if (multi_route.Count > 1)
{ // TODO: Maybe add some extra code for the the route-count is very low and chances of collisions are big.
// TODO: investigate what is more expensive, and extra random generation or creating a list and remove items.
// http://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle
// select a route.
int source_route_idx = OsmSharp.Math.Random.StaticRandomGenerator.Get().Generate(multi_route.Count);
int target_route_idx = -1;
do
{
target_route_idx = OsmSharp.Math.Random.StaticRandomGenerator.Get().Generate(multi_route.Count);
} while (source_route_idx == target_route_idx);
int source_count = multi_route.Sizes[source_route_idx];
int target_count = multi_route.Sizes[target_route_idx];
if (target_count > 0 && source_count > 3)
{
// take a part out of the orginal.
int size = (int)OsmSharp.Math.Random.StaticRandomGenerator.Get().Generate(source_count);
int source_location = OsmSharp.Math.Random.StaticRandomGenerator.Get().Generate(source_count);
int first = source_location - (size / 2);
if (first < 0)
{
first = 0;
}
//first = multi_route.StartOf(source_route_idx) + first;
int last = source_location + (size / 2);
if (last > source_count - 1)
{
last = source_count - 1;
}
//last = multi_route.StartOf(source_route_idx) + last;
int idx = -1;
IRoute source = multi_route.Route(source_route_idx);
List <int> part_of_orginal = new List <int>();
foreach (int customer in source)
{
idx++;
if (idx >= first && idx <= last)
{
part_of_orginal.Add(customer);
}
}
// remove from the source.
foreach (int customer in part_of_orginal)
{
multi_route.RemoveCustomer(customer);
}
// place it somewhere in the target.
if (part_of_orginal.Count > 0)
{
IRoute target = multi_route.Route(target_route_idx);
CheapestInsertionResult route_placement = CheapestInsertionHelper.CalculateBestPlacement(
solver.Problem, target, part_of_orginal[0], part_of_orginal[part_of_orginal.Count - 1]);
int from = route_placement.CustomerBefore;
foreach (int customer in part_of_orginal)
{
target.InsertAfter(from, customer);
//target.InsertAfterAndRemove(from, customer, -1);
from = customer;
}
}
}
}
return(new Individual <MaxTimeSolution, MaxTimeProblem, Fitness>(multi_route));
}
internal override MaxTimeSolution Solve(MaxTimeProblem problem)
{
MaxTimeCalculator calculator = new MaxTimeCalculator(
problem);
// generate a ATSP solution.
IRoute tsp_solution = _tsp_solution;
if (tsp_solution == null)
{
tsp_solution = _tsp_solver.Solve(new TSPProblem(problem));
}
// generate subtours from this solution.
MaxTimeSolution solution = new MaxTimeSolution(problem.Size, true);
// select a random start point.
int start = OsmSharp.Math.Random.StaticRandomGenerator.Get().Generate(problem.Size);
// start the first tour.
int placed = 0;
int previous = -1;
// place the first customer.
double weight = 0;
double total_weight = 0;
IRoute route = solution.Add(start);
previous = start;
while (placed < problem.Size)
{
// get the next customer from the tsp solution.
int next = tsp_solution.GetNeigbours(previous)[0];
// get the weight to the current start.
double weight_to_next = problem.WeightMatrix[previous][next];
double weight_to_start = problem.WeightMatrix[next][start];
total_weight = calculator.CalculateOneRouteIncrease(
weight, weight_to_next + weight_to_start);
weight = calculator.CalculateOneRouteIncrease(
weight, weight_to_next);
if (total_weight > problem.Max.Value)
{ // start a new route.
route = solution.Add(next);
weight = 0;
}
else
{ // just insert the next customer.
route.InsertAfter(previous, next);
//route.InsertAfterAndRemove(previous, next, -1);
}
// set the previous.
previous = next;
placed++;
}
if (!solution.IsValid())
{
throw new Exception();
}
StringBuilder builder = new StringBuilder();
builder.Append("[");
total_weight = 0;
for (int idx = 0; idx < solution.Count; idx++)
{
//IRoute route = routes.Route(idx);
route = solution.Route(idx);
weight = calculator.CalculateOneRoute(route);
builder.Append(" ");
builder.Append(weight);
builder.Append(" ");
total_weight = total_weight + weight;
}
builder.Append("]");
builder.Append(total_weight);
builder.Append(": ");
builder.Append(calculator.Calculate(solution));
Console.WriteLine(builder.ToString());
return(solution);
}
private void FillRoutes(MaxTimeCalculator calculator, MaxTimeSolution route1, MaxTimeSolution solution,
MaxTimeProblem problem)
{
double[] weights = new double[solution.Count];
// insert all non-placed customers in the order of the first route.
HashSet <int> unplaced = new HashSet <int>();
for (int route_idx = 0; route_idx < route1.Count; route_idx++)
{
IRoute route1_route = route1.Route(route_idx);
foreach (int customer in route1_route)
{
if (!solution.Contains(customer))
{
unplaced.Add(customer);
}
}
}
for (int idx = 0; idx < solution.Count; idx++)
{
IRoute route = solution.Route(idx);
weights[idx] = calculator.CalculateOneRoute(route);
}
// insert all non-placed customers in the order of the first route.
//for (int route_idx = 0; route_idx < route1.Count; route_idx++)
//{
// IRoute route1_route = route1.Route(route_idx);
// foreach (int customer in route1_route)
// {
// if (!solution.Contains(customer))
// {
while (unplaced.Count > 0)
{
int customer = unplaced.First <int>();
// try reinsertion.
CheapestInsertionResult result = new CheapestInsertionResult();
result.Increase = double.MaxValue;
int target_idx = -1;
CheapestInsertionResult unlimited_result = new CheapestInsertionResult();
unlimited_result.Increase = double.MaxValue;
int unlimited_target_idx = -1;
for (int idx = 0; idx < solution.Count; idx++)
{
IRoute route = solution.Route(idx);
CheapestInsertionResult current_result =
CheapestInsertionHelper.CalculateBestPlacement(problem.Weights, route, customer);
if (current_result.Increase < result.Increase)
{
if (weights[idx] + current_result.Increase < problem.Max.Value)
{
target_idx = idx;
result = current_result;
if (result.Increase <= 0)
{
break;
}
}
}
if (current_result.Increase < unlimited_result.Increase)
{
unlimited_target_idx = idx;
unlimited_result = current_result;
}
}
if (target_idx < 0)
{
result = unlimited_result;
target_idx = unlimited_target_idx;
}
// get the target route and insert.
IRoute target_route = solution.Route(target_idx);
weights[target_idx] = weights[target_idx] + result.Increase;
//target_route.InsertAfterAndRemove(result.CustomerBefore, result.Customer, result.CustomerAfter);
target_route.InsertAfter(result.CustomerBefore, result.Customer);
unplaced.Remove(result.Customer);
////solution.ToString();
//if (!solution.IsValid())
//{
// throw new Exception();
//}
}
// }
//}
}
/// <summary>
/// Test removing customers.
/// </summary>
public void DoTestRemove()
{
// create a new empty route.
const int count = 100;
IRoute route = this.BuildRoute(0, true);
var customers = new List <int>();
if (route != null)
{ // this part needs testing!
customers.Add(0);
for (int customer = 1; customer < count; customer++)
{
route.InsertAfter(customer - 1, customer);
//route.InsertAfterAndRemove(customer - 1, customer, -1);
customers.Add(customer);
}
// remove customers.
while (customers.Count > 0)
{
int customerIdx = OsmSharp.Math.Random.StaticRandomGenerator.Get().Generate(
customers.Count);
int customer = customers[customerIdx];
customers.RemoveAt(customerIdx);
route.Remove(customer);
Assert.AreEqual(customers.Count, route.Count);
Assert.AreEqual(customers.Count == 0, route.IsEmpty);
Assert.AreEqual(true, route.IsRound);
Assert.AreEqual(route.Last, route.First);
}
}
route = this.BuildRoute(true);
customers = new List <int>();
if (route != null)
{ // this part needs testing!
for (int customer = 0; customer < count; customer++)
{
route.InsertAfter(customer - 1, customer);
//route.InsertAfterAndRemove(customer - 1, customer, -1);
customers.Add(customer);
}
// remove customers.
while (customers.Count > 0)
{
int customerIdx = OsmSharp.Math.Random.StaticRandomGenerator.Get().Generate(
customers.Count);
int customer = customers[customerIdx];
customers.RemoveAt(customerIdx);
route.Remove(customer);
Assert.AreEqual(customers.Count, route.Count);
Assert.AreEqual(customers.Count == 0, route.IsEmpty);
Assert.AreEqual(true, route.IsRound);
Assert.AreEqual(route.Last, route.First);
}
}
}
public void TestDepotDynamicAsymmetricMultiRouteExchanges()
{
// create two routes.
// 0->11->12->13->14->15->0
// 0->21->22->23->24->25->0
var multiRoute = new MaxTimeSolution(0);
IRoute route1 = multiRoute.Add();
var customers = new List <int>(route1);
Assert.AreEqual(1, customers.Count);
Assert.AreEqual(0, customers[0]);
route1.InsertAfter(0, 11);
Assert.AreEqual("0->11", route1.ToString());
route1.InsertAfter(11, 12);
route1.InsertAfter(12, 13);
route1.InsertAfter(13, 14);
route1.InsertAfter(14, 15);
IRoute route2 = multiRoute.Add();
customers = new List <int>(route2);
Assert.AreEqual(1, customers.Count);
Assert.AreEqual(0, customers[0]);
route2.InsertAfter(0, 21);
Assert.AreEqual("0->21", route2.ToString());
route2.InsertAfter(21, 22);
route2.InsertAfter(22, 23);
route2.InsertAfter(23, 24);
route2.InsertAfter(24, 25);
customers = new List <int>(route1);
Assert.AreEqual(6, customers.Count);
Assert.AreEqual(0, customers[0]);
Assert.AreEqual(11, customers[1]);
Assert.AreEqual(12, customers[2]);
Assert.AreEqual(13, customers[3]);
Assert.AreEqual(14, customers[4]);
Assert.AreEqual(15, customers[5]);
customers = new List <int>(route2);
Assert.AreEqual(6, customers.Count);
Assert.AreEqual(0, customers[0]);
Assert.AreEqual(21, customers[1]);
Assert.AreEqual(22, customers[2]);
Assert.AreEqual(23, customers[3]);
Assert.AreEqual(24, customers[4]);
Assert.AreEqual(25, customers[5]);
// replace the entire first route.
route1.ReplaceEdgeFrom(0, 0);
route2.ReplaceEdgeFrom(25, 11);
route2.ReplaceEdgeFrom(11, 12);
route2.ReplaceEdgeFrom(12, 13);
route2.ReplaceEdgeFrom(13, 14);
route2.ReplaceEdgeFrom(14, 15);
Assert.IsTrue(multiRoute.IsValid());
// create two routes.
// 0->11->12->13->14->15->0
// 0->21->22->23->24->25->0
multiRoute = new MaxTimeSolution(0);
route1 = multiRoute.Add();
customers = new List <int>(route1);
Assert.AreEqual(1, customers.Count);
Assert.AreEqual(0, customers[0]);
route1.InsertAfter(0, 11);
Assert.AreEqual("0->11", route1.ToString());
route1.InsertAfter(11, 12);
route1.InsertAfter(12, 13);
route1.InsertAfter(13, 14);
route1.InsertAfter(14, 15);
route2 = multiRoute.Add();
customers = new List <int>(route2);
Assert.AreEqual(1, customers.Count);
Assert.AreEqual(0, customers[0]);
route2.InsertAfter(0, 21);
Assert.AreEqual("0->21", route2.ToString());
route2.InsertAfter(21, 22);
route2.InsertAfter(22, 23);
route2.InsertAfter(23, 24);
route2.InsertAfter(24, 25);
// exchange parts.
var part1 = new List <int>(route1.Between(11, 13));
var part2 = new List <int>(route2.Between(23, 25));
route1.ReplaceEdgeFrom(0, 14);
route2.ReplaceEdgeFrom(22, 0);
int previous = 0;
for (int idx = 0; idx < part2.Count; idx++)
{
route1.ReplaceEdgeFrom(previous, part2[idx]);
previous = part2[idx];
}
route1.ReplaceEdgeFrom(previous, 14);
previous = 22;
for (int idx = 0; idx < part1.Count; idx++)
{
route2.ReplaceEdgeFrom(previous, part1[idx]);
previous = part1[idx];
}
route2.ReplaceEdgeFrom(previous, 0);
Assert.IsTrue(multiRoute.IsValid());
customers = new List <int>(route1);
Assert.AreEqual(6, customers.Count);
Assert.AreEqual(0, customers[0]);
Assert.AreEqual(23, customers[1]);
Assert.AreEqual(24, customers[2]);
Assert.AreEqual(25, customers[3]);
Assert.AreEqual(14, customers[4]);
Assert.AreEqual(15, customers[5]);
customers = new List <int>(route2);
Assert.AreEqual(6, customers.Count);
Assert.AreEqual(0, customers[0]);
Assert.AreEqual(21, customers[1]);
Assert.AreEqual(22, customers[2]);
Assert.AreEqual(11, customers[3]);
Assert.AreEqual(12, customers[4]);
Assert.AreEqual(13, customers[5]);
// create two routes.
// 0->11->12->13->14->15->0
// 0->21->22->23->24->25->0
multiRoute = new MaxTimeSolution(0);
route1 = multiRoute.Add();
customers = new List <int>(route1);
Assert.AreEqual(1, customers.Count);
Assert.AreEqual(0, customers[0]);
route1.InsertAfter(0, 11);
Assert.AreEqual("0->11", route1.ToString());
route1.InsertAfter(11, 12);
route1.InsertAfter(12, 13);
route1.InsertAfter(13, 14);
route1.InsertAfter(14, 15);
route2 = multiRoute.Add();
customers = new List <int>(route2);
Assert.AreEqual(1, customers.Count);
Assert.AreEqual(0, customers[0]);
route2.InsertAfter(0, 21);
Assert.AreEqual("0->21", route2.ToString());
route2.InsertAfter(21, 22);
route2.InsertAfter(22, 23);
route2.InsertAfter(23, 24);
route2.InsertAfter(24, 25);
route1.ReplaceEdgeFrom(12, 15);
route1.ReplaceEdgeFrom(14, 11);
route1.ReplaceEdgeFrom(0, 13);
customers = new List <int>(route1);
Assert.AreEqual(6, customers.Count);
Assert.AreEqual(0, customers[0]);
Assert.AreEqual(13, customers[1]);
Assert.AreEqual(14, customers[2]);
Assert.AreEqual(11, customers[3]);
Assert.AreEqual(12, customers[4]);
Assert.AreEqual(15, customers[5]);
route1.ToString();
}