//Our TSP
internal void solveProblemTabu()
{
int bssfUpdates = 0;
Algorithms algorithms = new Algorithms();
bssf = new TSPSolution(algorithms.greedy(Cities));
TSPSolution currentSolution = new TSPSolution(bssf.Route);
int size = Convert.ToInt32(Program.MainForm.textBoxTabuSize.Text);
TabuList tabuList = new TabuList(size);//set capacity of tabuList
int timeSeconds = Convert.ToInt32(Program.MainForm.textBoxTime.Text);
double totalTime = 0;
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
while(stopwatch.Elapsed.TotalSeconds < timeSeconds)//run for 600 seconds, 10 minutes
{
currentSolution = findBestCandidate(currentSolution, tabuList);
if(currentSolution.cost < bssf.cost)
{
bssf = new TSPSolution(currentSolution.Route);
totalTime = stopwatch.Elapsed.TotalSeconds;
bssfUpdates++;
}
tabuList.addSolution(currentSolution);
}
stopwatch.Stop();
Program.MainForm.tbCostOfTour.Text = " " + bssf.cost;
Program.MainForm.tbElapsedTime.Text = " " + totalTime;
//Program.MainForm.tbElapsedTime.Text = " " + stopwatch.Elapsed.TotalSeconds;
Program.MainForm.toolStripTextBox1.Text = " " + bssfUpdates;
//print bssf update number
// do a refresh.
Program.MainForm.Invalidate();
}
public TSPSolution findBestCandidate(TSPSolution currentSolution, TabuList tabuList)
{
TSPSolution bestCandidate = null;
TSPSolution candidate = new TSPSolution(new ArrayList(currentSolution.Route));
for (int swapA = 0; swapA < Cities.Length - 1; swapA++)
{
// only consider swapping forward so we don't double the space
for (int swapB = swapA + 1; swapB < Cities.Length; swapB++)
{
//candidate.Route.Clear();
// perform swap
City tmp = (City)candidate.Route[swapA];
candidate.Route[swapA] = candidate.Route[swapB];
candidate.Route[swapB] = tmp;
// normalize to make TabuList.Contains() easier
if (swapA == 0)
{
ArrayList normalRoute = new ArrayList();
for (int i = swapB; i < Cities.Length; i++)
normalRoute.Add(candidate.Route[i]);
for (int i = 0; i < swapB; i++)
normalRoute.Add(candidate.Route[i]);
candidate.Route = normalRoute;
}
// recalc cost
candidate.cost = candidate.costOfRoute();
// get best candidate
if (!tabuList.contains(candidate))
{
if (bestCandidate == null || candidate.cost < bestCandidate.cost){
bestCandidate = new TSPSolution(new ArrayList(candidate.Route));
}
}
// revert swap for next candidate
if (swapA == 0)
{
// it's simpler to recopy
candidate.Route = new ArrayList(currentSolution.Route);
}
else
{
candidate.Route[swapB] = candidate.Route[swapA];
candidate.Route[swapA] = tmp;
}
}
}
if (bestCandidate == null)
{
tabuList.setCapacity(tabuList.capacity * 2);
return tabuList.getLast(); // or whatever this function ends up being called
}
return bestCandidate;
}
