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cTSP.cs
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cTSP.cs
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using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace TSP
{
class cTSP
{
int num_citta,n1;
public float[,] distance;
float[,] distcopy; //per usarle in intere se necessario.
public int[,] sort_dist;
float[] x;
float[] y;
float tour_length;
int[] tour_path;
float max_x, max_y, min_x, min_y;
int[] chull;
int nchull;
public EDGE_LIST[] lb;
public int delta;
public EDGE_LIST[] pool_arcs; //significa che ho gli archi certi...
//da cui nodi posso eliminare tutti gli altri archi...
//ridurrei di molto l'insieme degli archi e velocizzerei...
public float[,] alpha;
public int[,] sort_alpha;
public int ALPHA_NN; //n° nodi di alpha nearest
public int ALPHA_NA; //n° archi
const int ALPHA_NN_MIN = 5;
public int ALPHA_NN_MAX = 50;
public MST mst;
bool computed_distance;
bool loaded_data;
public bool computed_tour;
public bool sorted_dist;
public bool computed_chull;
public bool computed_lb; //0 none 1=mst 2=1-tree 3=lb
public int[] degree_node;
public struct Node
{
public float x;
public float y;
public int city;
}
Stack<Node> stacknodes;
public Node Last_Popped;
public cTSP()
{
n1 = num_citta = nchull = 0;
tour_length=0;
computed_distance=false;
loaded_data=false;
computed_tour = false;
max_x = max_y = float.MinValue;
min_x = min_y = float.MaxValue;
sorted_dist = false;
computed_chull = false;
computed_lb = false;
mst = null;
degree_node = new int[num_citta];
//int delta = (int)(Math.Round(Math.Sqrt(num_citta) /*+ Math.Log10(num_citta)*/));
delta = 0;
}
public void Build_pool_arcs(bool strong)
{
int i, j,n;
n=num_citta;
bool[] mark = new bool[n];
List<EDGE_LIST> arcs = new List<EDGE_LIST>();
EDGE_LIST ed;
int A, B, C, D;
for (i = 0; i < n; i++)
{
if (mark[i])
continue;
A = i;
B = sort_dist[A, 1];
C = sort_dist[A, 2]; //2° + vic di A
D = sort_dist[B, 2]; //2° + vic di B
//E = sort_dist[B, 1];
if (D == A) //allora b dinveta a
{
mark[i] = true;
if (mark[B])
continue;
B = sort_dist[A, 1];
C = sort_dist[A, 2]; //2° + vic di A
D = sort_dist[B, 2];
i = 0;
}
//if ((mark[A]) && (mark[B]))
// continue;
//nienete else perchè dal caso sopra mi ritroverò in uno dei 2 seguenti...
if (D == C) //allora AB tour ottimo.
{
if (strong)
{
if (A < B)
{
ed.a = A;
ed.b = B;
}
else
{
ed.b = A;
ed.a = B;
}
arcs.Add(ed);
}
//altrimenti non lo inserisco per non rischiare troppo!!!
}
else // caso in cui a,b,c,d 4 nodi diversi
{
float rAC = distance[A, C];
float rBD = distance[B, D];
if ((rAC > distance[A, B]) &&
(rBD > distance[A, B]))
{
if (A < B)
{
ed.a = A;
ed.b = B;
}
else
{
ed.b = A;
ed.a = B;
}
arcs.Add(ed);
}
//prova
else
{
if ((rAC < distance[A, D])&&
(distance[B,C]>rBD))
{
if (A < C)
{
ed.a = A;
ed.b = C;
}
else
{
ed.b = A;
ed.a = C;
}
arcs.Add(ed);
//è più stringente con questo arco sotto in +
if (strong)
{
if (B < D)
{
ed.a = B;
ed.b = D;
}
else
{
ed.a = D;
ed.b = B;
}
arcs.Add(ed);
}
}
}
}
mark[A] = true;
//mark[B] = true;
}
//rimuovo archi doppi...
for (i = 0; i < arcs.Count; i++)
{
ed = arcs[i];
for (j = i + 1; j < arcs.Count; j++)
{
if ((ed.a == arcs[j].a)&&(ed.b==arcs[j].b))
{
arcs.RemoveAt(j);
j--;
i = 0;
}
}
}
pool_arcs = arcs.ToArray();
//in modo ridondante posso escludere gli archi dei nodi dei pool...
}
//da pool_arcs riduzione grafo dei nodi degli archi certi...
//da mettere a posto quest'idea e l'algoritmo...
public void Graph_reduction(bool strong)
{
Build_pool_arcs(strong);
Node n0 = new Node();
Node n1 = new Node();
stacknodes = new Stack<Node>();
for (int i = 0; i<pool_arcs.Length; i++)
{
n0.city = pool_arcs[i].a;
n1.city = pool_arcs[i].b;
n0.x = x[n0.city];
n0.y = y[n0.city];
n1.x = x[n1.city];
n1.y = y[n1.city];
stacknodes.Push(n0);
stacknodes.Push(n1);
Collapse1Node(n0, n1, true);
for (int j = i + 1; j < pool_arcs.Length; j++)
{
//sistemo l'array per il dopo collasso..
if(pool_arcs[j].a >= n1.city)
pool_arcs[j].a--;
if(pool_arcs[j].b >= n1.city)
pool_arcs[j].b--;
}
}
//ricalcolare le sort_distance..
this.n1 = num_citta - 1;
sort_distances();
}
public int GetNN_Node(int node, int nn)
{
return sort_dist[node, nn];
}
public cTSP(int n)
{
num_citta=n;
n1 = n - 1;
distance = new float[n,n];
x = new float[n];
y = new float[n];
tour_path = new int[n];
tour_length = 0;
computed_distance = false;
loaded_data = false;
max_x = max_y = float.MinValue;
min_x = min_y = float.MaxValue;
computed_tour = false;
sort_dist = new int[n, n];
sorted_dist = false;
computed_lb = false;
degree_node = new int[num_citta];
mst = new MST(n);
//è lo stesso numero che usa Alphanearness in automatico come stima di nodi vicini.
//perchè mi sembra sensato che sia in proporzione al numero di nodi che statico e fissato sperimentalmente.
delta = (int)(Math.Round(Math.Sqrt(num_citta) + Math.Log10(num_citta)));
}
public float[,] GetDistanceMatrix()
{
return distance;
}
public void SetIntDistanceMatrix()
{
int i, j;
distcopy = new float[num_citta, num_citta];
for (i = 0; i < num_citta; i++)
{
distcopy[i, i] = 0;
for (j = i + 1; j < num_citta; j++)
{
distcopy[i, j] = distcopy[j, i] = distance[i, j];
distance[i, j] = distance[j, i] = (float)Math.Round(distance[i, j]);
}
}
}
public void ResetDistanceMatrix()
{
if (distcopy == null)
return;
int i, j;
for (i = 0; i < num_citta; i++)
{
//distcopy[i, i] = 0;
for (j = i + 1; j < num_citta; j++)
{
distance[i, j] = distance[j, i] = distcopy[i, j];
}
}
distcopy = null;
}
public void Reset_Data()
{
loaded_data = false;
min_x = min_y = float.MaxValue;
max_x = max_y = float.MinValue;
distance = null;
sort_dist = null;
alpha = null;
sort_alpha = null;
sorted_dist = false;
distcopy = null;
tour_path = null;
num_citta=n1=0;
x=y=null;
tour_length=0;
chull=null;
nchull=0;
lb=null;
mst=null;
computed_distance=false;
computed_tour=computed_chull=computed_lb=false;
degree_node = null; ;
}
public void Loaded_Data()
{
loaded_data=true;
//trovare il valore max e min per la visualizzazione su schermo
}
public void Loaded_Data(bool b)
{
loaded_data = b;
//trovare il valore max e min per la visualizzazione su schermo
}
public void setNode(int i, float _x, float _y)
{
x[i] = _x;
y[i] = _y;
if (_x > max_x)
max_x = _x;
if (_y > max_y)
max_y = _y;
if (_x < min_x)
min_x = _x;
if (_y < min_y)
min_y = _y;
}
public float ComputeDistance(int i, int j)
{
float dx, dy;
dx = x[i] - x[j];
dy = y[i] - y[j];
return distance[i, j] = Convert.ToSingle(Math.Sqrt(dx * dx + dy * dy));
}
public void ComputeDistance(int i, int j, float value)
{
distance[i, j] = value;
}
public void Computed_distance()
{
computed_distance = true;
}
public float GetDistance(int i, int j)
{
return distance[i, j];
}
public bool isLoaded()
{
if (loaded_data)
return true;
else
return false;
}
public bool isOK()
{
if ((loaded_data) && (computed_distance))
return true;
else
return false;
}
public int GetN()
{
return num_citta;
}
public float Get_x(int i)
{
return x[i];
}
public float Get_y(int i)
{
return y[i];
}
public void RecalcultateCoordMinMaxXY()
{
max_y = max_x = float.MinValue;
min_y = min_x = float.MaxValue;
for (int i = 0; i < num_citta; i++)
{
if (x[i] > max_x)
max_x = x[i];
if (x[i] < min_x)
min_x = x[i];
if (y[i] > max_y)
max_y = y[i];
if (y[i] < min_y)
min_y = y[i];
}
}
public float GetMax_x()
{
return max_x;
}
public float GetMax_y()
{
return max_y;
}
public float GetMin_x()
{
return min_x;
}
public float GetMin_y()
{
return min_y;
}
public void InsertNode(float _x, float _y)
{
}
public float Calculate_tour_length()
{
int i;
if (!computed_tour)
return 0;
tour_length = 0;
for (i = 0; i < num_citta - 1; i++)
tour_length += distance[tour_path[i], tour_path[i + 1]];
tour_length+=distance[tour_path[i],tour_path[0]];
return tour_length;
}
public int Calculate_int_tour_length()
{
int i;
int tour_length = 0;
for (i = 0; i < num_citta - 1; i++)
tour_length += (int) Math.Round(distance[tour_path[i], tour_path[i + 1]]);
tour_length += (int) Math.Round(distance[tour_path[i], tour_path[0]]);
return tour_length;
}
public int GetTourNode(int i)
{
return tour_path[i];
}
public void Reset_tour()
{
int i;
if (!loaded_data)
return;
for (i = 0; i < num_citta; i++)
tour_path[i] = num_citta;
tour_length = 0;
computed_tour = false;
}
public void Sequential_tour()
{
int i;
for (i = 0; i < num_citta; i++)
tour_path[i] = i;
computed_tour = true;
}
public void Random_tour()
{
int i,j,k;
Random rand = new Random();
for(i=0;i<num_citta;i++)
tour_path[i]=-1;
for (i = 0; i < n1; )
{
k=rand.Next(num_citta );
for (j = 0; j < n1; j++)
{
if (k == tour_path[j])
break;
}
if (j == n1)
{
tour_path[i] = k;
i++;
}
}
for (j = 0; j < num_citta; j++)
{
for (i = 0; i < num_citta; i++)
{
if (j == tour_path[i])
break;
}
if (i == num_citta) //ho trovato il valore.
{
tour_path[num_citta - 1] = j;
j = num_citta;
break;
}
}
computed_tour = true;
}
private void Quick_Sort_pi(int[] ipi, float[] pi, int p, int r, int p0)
{
int q;
if (p < r)
{
q = Quick_Sort_pi_Partition(ipi, pi, p, r,p0);
Quick_Sort_pi(ipi, pi, p, q,p0);
Quick_Sort_pi(ipi, pi , (q + 1), r,p0);
}
}
private int Quick_Sort_pi_Partition(int[] ipi, float[] pi, int p, int r, int p0)
{
float x;
int i, j;
x = pi[ipi[p]];
i = p - 1;
j = r + 1;
while (true)
{
do
{
j--;
} while (pi[ipi[j]] > x);
do
{
i++;
} while (pi[ipi[i]] < x);
if (i < j)
{
if (pi[ipi[i]] == pi[ipi[j]])
{
if (distance[ipi[i], p0] < distance[ipi[j], p0])
{
p = ipi[i];
ipi[i] = ipi[j];
ipi[j] = p;
}
else
{
}
}
else
{
p = ipi[i];
ipi[i] = ipi[j];
ipi[j] = p;
}
}
else return j;
}
}
private void Quick_Sort_dist(int idist, int p, int r)
{
int q;
if (p < r)
{
q = Quick_Sort_dist_Partition(idist, p, r);
Quick_Sort_dist(idist, p, q);
Quick_Sort_dist(idist, (q + 1), r);
}
}
private int Quick_Sort_dist_Partition(int idist, int p, int r)
{
float x;
int i, j;
x = distance[idist,sort_dist[idist,p]];
i = p - 1;
j = r + 1;
while (true)
{
do
{
j--;
} while (distance[idist,sort_dist[idist,j]] > x);
do
{
i++;
} while (distance[idist,sort_dist[idist,i]] < x);
if (i < j)
{
p = sort_dist[idist,i];
sort_dist[idist,i] = sort_dist[idist,j];
sort_dist[idist,j] = p;
}
else return j;
}
}
private void Quick_Sort_dist_Alpha(int idist, int p, int r)
{
int q;
if (p < r)
{
q = Quick_Sort_dist_Partition_Alpha(idist, p, r);
Quick_Sort_dist_Alpha(idist, p, q);
Quick_Sort_dist_Alpha(idist, (q + 1), r);
}
}
private int Quick_Sort_dist_Partition_Alpha(int idist, int p, int r)
{
float x;
int i, j;
x = distance[idist, sort_alpha[idist, p]];
i = p - 1;
j = r + 1;
while (true)
{
do
{
j--;
} while (distance[idist, sort_alpha[idist, j]] > x);
do
{
i++;
} while (distance[idist, sort_alpha[idist, i]] < x);
if (i < j)
{
p = sort_alpha[idist, i];
sort_alpha[idist, i] = sort_alpha[idist, j];
sort_alpha[idist, j] = p;
}
else return j;
}
}
private bool Check_TOUR(int n)
{
int i, j, k;
bool ret = true;
//check
for (i = 0; i < n; i++)
{
for (j = 0, k = 0; j < n; j++)
{
if (i == tour_path[j])
k++;
}
if ((k > 1) || (k == 0))
{
computed_tour = false;
ret = false;
break;
}
}
return ret;
}
public void sort_distances()
{
int i,j;
for (i = 0; i < num_citta; i++)
{
for (j = 0; j < num_citta; j++)
sort_dist[i, j] = j;
Quick_Sort_dist(i, 0, n1);
}
sorted_dist = true;
}
public void NeirestN_tour(int node_start)
{
int i,j,k,nn;
//int[] sort = new int[num_citta];
Reset_tour();
tour_path[0] = node_start;
nn = 1;
while(nn<num_citta)
{
//for (j = 0; j < num_citta; j++)
// sort[j] = j;
//Quick_Sort_dist(sort, tour_path[i], 0, n1);
//controllo il primo da mettere...
i = tour_path[nn - 1];
for(k=0;k<num_citta;k++)
{
for (j = 0; j < nn; j++)
{
if (tour_path[j] == sort_dist[i,k])
break;
}
if (j == nn)
{
tour_path[nn] = sort_dist[i,k];
nn++;
break;
}
}
}
}
public bool isToured()
{
return computed_tour;
}
public float UpdateTourLength(float d)
{
return tour_length += d;
}
public void setTourNode(int i, int node)
{
tour_path[i]=node;
}
private float CCW(int i1, int i2, int i3)
{
return (x[i2] - x[i1]) * (y[i3] - y[i1]) -
(y[i2] - y[i1]) * (x[i3] - x[i1]);
}
private int[] AngularySort(int p0)
{
int[] sorted;
float[] pi;
int i;
pi = new float[num_citta];
sorted = new int[num_citta];
for (i = 0; i < num_citta; i++)
{
sorted[i] = i;
pi[i] = ((x[p0] - x[i]) / distance[p0, i]);
}
pi[p0] = -1;
Quick_Sort_pi(sorted, pi, 0, n1,p0);
return sorted;
}
private int DownRight()
{
int i, p0;
for (i = 1, p0 = 0; i < num_citta; i++)
{
if (y[p0] > y[i])
p0 = i;
else
if ((y[p0] == y[i]) && (x[p0] < x[i]))
p0 = i;
}
return p0;
}
public int ConvexHull()
{
int p0;
int[] sorted;
int i, j;
float cp;
p0 = DownRight();
sorted = AngularySort(p0);
chull = new int[num_citta];
chull[0] = sorted[0]; chull[1] = sorted[1];
for (i = 2, j = 1; i < num_citta; i++)
{
cp = CCW(sorted[i], chull[j], chull[j - 1]);
if (cp <= 0)
{
if (cp==0)
{
if (distance[chull[j - 1], chull[j]] > distance[chull[j - 1], sorted[i]])
{
chull[j + 1] = chull[j];
chull[j] = sorted[i];
j++;
}
else if(distance[sorted[i],sorted[i-1]]==0) // è come se fosse lo stesso punto...
{
continue;
}
else
chull[++j] = sorted[i];
}
else
chull[++j] = sorted[i];
}
else
{
while ((cp > 0) && (j > 1))
{
j--;
//chull[--j2] = chull[--j];
cp = CCW(sorted[i], chull[j], chull[j - 1]);
}
chull[++j] = sorted[i];
}
}
computed_chull = true;
return nchull=j+1;
}
public int GetNChull()
{
return nchull;
}
public int GetChull_Node(int i)
{
return chull[i];
}
public void CheapestInsertion()
{
int n_ch,n_ch1; // numero città convex hull;
int i,i2,j,j2; //contatori
float d1,d2; //numeri per le distanze
int bestj,besti,bestj2; // indici
float[] min_dist; //vettore di indici delle distanze minori.
int[] min_d_i; //indice dell'arco relativo alle dist.
//Calcolo del convex hull
//if(!computed_chull)
Reset_tour();
ConvexHull();
n_ch=nchull;
//alloco la matrice. delle distanze minime
n_ch1=nchull-1;
min_d_i = new int[num_citta];
min_dist = new float[num_citta];
//OverHead
for (i = 0; i < nchull; i++)
tour_path[i] = chull[i];
for (i = 0,j2=nchull; ((i < num_citta)&&(j2<num_citta)); i++)
{
for (j = 0; j < num_citta; j++)
{
if (i == tour_path[j])
break;
}
if (j == num_citta)
tour_path[j2++] = i;
}
//calcolo le distanze minime di ogni punto con ogni arco.
for(i=nchull;i<num_citta;i++)
{
min_dist[i]=float.MaxValue;
for(j=0,i2=1;j<n_ch1;j++,i2++)
{
d1 = distance[tour_path[j],tour_path[i2]];
d2 = distance[tour_path[i],tour_path[j]] +
distance[tour_path[i],tour_path[i2]];
d2 -= d1;
if(d2<min_dist[i])
{
min_dist[i]=d2;
min_d_i[i]=j;
}
}
//l'ltimo col primo
d2 = (distance[tour_path[i],tour_path[j]] +
distance[tour_path[i],tour_path[0]])-
distance[tour_path[j],tour_path[0]];
if(d2<min_dist[i])
{
min_dist[i]=d2;
min_d_i[i]=j;
}
}
//ora cerco dai punti non inseriti l'arco migliore.
while(n_ch<num_citta)
{
d1=float.MaxValue;
for(i=n_ch,besti=n_ch;i<num_citta;i++)
{
if(min_dist[i]<d1)
{
d1 = min_dist[i];
besti=i;
}
}
//inserisco il punto besti tra bestj e bestj+1
j=tour_path[besti];
bestj=min_d_i[besti]+1;
for(i2=besti;i2>bestj;i2--)
tour_path[i2] = tour_path[i2-1];
tour_path[bestj]=j;
//controllo che il vettore delle distanze non sia shiftato.
if(besti>n_ch)
{
for(i2=besti,j=besti-1;i2>n_ch;i2--,j--)
{
min_dist[i2]=min_dist[j];
min_d_i[i2]=min_d_i[j];
}
}
//Aggiorno le distanze minime fra i nodi e gli archi.
n_ch1=n_ch++;
j=bestj-1;
if(bestj<n_ch1)
bestj2=bestj+1;
else
bestj2=0;
for(i=n_ch;i<num_citta;i++)
{
d2 = (distance[tour_path[i],tour_path[j]] +
distance[tour_path[i],tour_path[bestj]])-
distance[tour_path[j],tour_path[bestj]];