Example #1
0
        private void Greedy(int firstCity)
        {
            Tour       tour          = new Tour();
            List <int> notUsedCities = new List <int>();
            double     tourLength    = 0;

            for (int i = 0; i < numberOfCities; i++)
            {
                notUsedCities.Add(i);
            }

            tour.Add(firstCity);
            notUsedCities.Remove(firstCity);
            while (notUsedCities.Count > 0)
            {
                int    actualNodeNumber = tour[tour.Count - 1];
                double minLength        = Double.MaxValue;
                int    chosenNode       = -1;

                foreach (int nodeNumber in notUsedCities)
                {
                    double length = distancesBetweenCities[actualNodeNumber, nodeNumber];
                    if (length < minLength)
                    {
                        minLength  = length;
                        chosenNode = nodeNumber;
                    }
                }

                tourLength += minLength;
                tour.Add(chosenNode);
                notUsedCities.Remove(chosenNode);
            }
            tourPopulation.Add(tour);
        }
Example #2
0
        private Tour findReplacement(Tour Next, Tour Prev)
        {
            Tour B = new Tour();
            int  k, p;

            for (int i = 0; i < Prev.Count; i++)
            {
                k = Next.IndexOf(Prev[i]);
                p = k;
                if (k == numberOfCities - 1)
                {
                    p = 0;
                }
                else
                {
                    p += 1;
                }
                if (i != Next.Count - 1)
                {
                    if (Next[p] != Prev[i + 1])
                    {
                        B.Add(Next[p]);
                    }
                }
                else
                {
                    if (Next[p] != Prev[0])
                    {
                        B.Add(Next[p]);
                    }
                }
            }
            return(B);
        }
Example #3
0
        private void Crossover(Tour parent1, Tour parent2, Tour child)
        {
            int unique = 0;

            child.Clear();
            int        index = 0;
            int        start = rand.Next(0, numberOfCities * 6 / 10);
            int        len   = rand.Next(numberOfCities * 3 / 10, (numberOfCities - 1 - start));
            List <int> S;

            S = parent1.GetRange(start, len);
            int i = 0;

            while (index < start)
            {
                if (!S.Contains(parent2[i]))
                {
                    child.Add(parent2[i]);
                    index++;
                }
                else
                {
                    unique++;
                }
                i++;
            }
            child.AddRange(S);
            index += len;
            while (index < parent1.Count())
            {
                if (!S.Contains(parent2[i]))
                {
                    unique++;
                    child.Add(parent2[i]);
                    index++;
                }
                else
                {
                    unique++;
                }
                i++;
            }
            if (unique == numberOfCities - len)
            {
                Mutate(child);
            }
        }
Example #4
0
        private Tour generateRandomTour()
        {
            Tour       tour         = new Tour();
            List <int> notUsedNodes = new List <int>();

            for (int i = 0; i < numberOfCities; i++)
            {
                notUsedNodes.Add(i);
            }
            for (int i = numberOfCities; i > 0; i--)
            {
                int random = rand.Next(i);
                tour.Add(notUsedNodes[random]);
                notUsedNodes.RemoveAt(random);
            }
            return(tour);
        }