private static int[] TopologicalSorting(GraphAdjAlt0 g)
{
int n = g.v.Length;
marked = new int[n];
reversePost = new Stack<int>();
for (int v = 0; v < n; v++)
{
if (marked[v] != 0)
{
continue;
}
DFS(g, v);
}
int[] r = new int[reversePost.Count];
int i = 0;
while (reversePost.Count != 0)
{
r[i] = reversePost.Pop() + 1;
i++;
}
return r;
}
public DataDirectedGraphsAlt0(string fileName)
{
string filePath = Utils.GetFullFilePath(fileName);
try
{
using (StreamReader reader = new StreamReader(filePath))
{
string line;
int iGraph = -1;
int countVerticles;
int countEdges = 0;
line = reader.ReadLine();
Count = int.Parse(line);
Graphs = new GraphAdjAlt0[Count];
while ((line = reader.ReadLine()) != null)
{
if (line == "")
{
continue;
}
if (countEdges == 0)
{
iGraph++;
string[] args = line.Split(' ');
countVerticles = int.Parse(args[0]);
countEdges = int.Parse(args[1]);
Graphs[iGraph] = new GraphAdjAlt0();
Graphs[iGraph].v = new List<int>[countVerticles];
for (int i = 0; i < Graphs[iGraph].v.Length; i++)
{
Graphs[iGraph].v[i] = new List<int>();
}
continue;
}
string[] edge = line.Split(' ');
int v0 = int.Parse(edge[0]) - 1;
int v1 = int.Parse(edge[1]) - 1;
Graphs[iGraph].v[v0].Add(v1);
countEdges--;
}
}
}
catch (Exception e)
{
Console.WriteLine("The file could not be read:");
Console.WriteLine(e.Message);
}
}
private static int[] HamiltonianPath(GraphAdjAlt0 g)
{
int[] r = TopologicalSorting(g);
// next vertix (with index i + 1) must finding in
// list of previous vertix (with index i), becouse must be edge
// beetween them
for(int i = 0; i < r.Length - 1; i++)
{
if (g.v[r[i] - 1].IndexOf(r[i + 1] - 1) == -1)
{
return new int[] { -1 };
}
}
int[] rr = new int[r.Length + 1];
Array.Copy(r, 0, rr, 1, r.Length);
rr[0] = 1;
return rr;
}
private static void DFS(GraphAdjAlt0 g, int v)
{
marked[v] = 1;
if (null != g.v[v])
{
foreach (int i in g.v[v])
{
if (marked[i] != 0)
{
continue;
}
DFS(g, i);
}
}
reversePost.Push(v);
}