/// <summary>
/// Determines whether the edge-weighted digraph <tt>G</tt> has a topological
/// order and, if so, finds such an order.
/// </summary>
/// <param name="g">g the edge-weighted digraph</param>
public Topological(EdgeWeightedDigraph g)
{
var finder = new EdgeWeightedDirectedCycle(g);
if (!finder.HasCycle())
{
var dfs = new DepthFirstOrder(g);
_order = dfs.ReversePost();
}
}
/// <summary>
/// Determines whether the edge-weighted digraph <tt>G</tt> has a topological
/// order and, if so, finds such an order.
/// </summary>
/// <param name="g">g the edge-weighted digraph</param>
public Topological(EdgeWeightedDigraph g)
{
var finder = new EdgeWeightedDirectedCycle(g);
if (!finder.HasCycle())
{
var dfs = new DepthFirstOrder(g);
_order = dfs.ReversePost();
}
}
private readonly int[] _rank; // rank[v] = position of vertex v in topological order
#endregion Fields
#region Constructors
/// <summary>
/// Determines whether the digraph <tt>G</tt> has a topological order and, if so,
/// finds such a topological order.
/// </summary>
/// <param name="g">g the digraph</param>
public Topological(Digraph g)
{
var finder = new DirectedCycle(g);
if (!finder.HasCycle())
{
var dfs = new DepthFirstOrder(g);
_order = dfs.ReversePost();
_rank = new int[g.V];
var i = 0;
foreach (int v in _order)
_rank[v] = i++;
}
}
private readonly int[] _rank; // rank[v] = position of vertex v in topological order
/// <summary>
/// Determines whether the digraph <tt>G</tt> has a topological order and, if so,
/// finds such a topological order.
/// </summary>
/// <param name="g">g the digraph</param>
public Topological(Digraph g)
{
var finder = new DirectedCycle(g);
if (!finder.HasCycle())
{
var dfs = new DepthFirstOrder(g);
_order = dfs.ReversePost();
_rank = new int[g.V];
var i = 0;
foreach (int v in _order)
{
_rank[v] = i++;
}
}
}
public void Run()
{
Console.WriteLine("Choose file:"); // Prompt
Console.WriteLine("1 - tinyDAG.txt"); // Prompt
Console.WriteLine("or quit"); // Prompt
var fileNumber = Console.ReadLine();
string fileName;
switch (fileNumber)
{
case "1":
fileName = "tinyDAG.txt";
break;
case "quit":
return;
default:
return;
}
var @in = new In($"Files\\Graphs\\{fileName}");
var lines = @in.ReadAllLines();
var lineIterator = 0;
var v = 0;
var e = 0;
var edges = new List<EdgeD>();
foreach (var line in lines)
{
if (lineIterator == 0)
{
v = Convert.ToInt32(line);
}
if (lineIterator == 1)
{
e = Convert.ToInt32(line);
}
if (lineIterator > 1)
{
var lineSplitted = line.Split(new[] {' '}, StringSplitOptions.RemoveEmptyEntries);
var ve = Convert.ToInt32(lineSplitted[0]);
var we = Convert.ToInt32(lineSplitted[1]);
var edge = new EdgeD(ve, we);
edges.Add(edge);
}
lineIterator++;
}
var digraph = new Digraph(v, e, edges);
Console.WriteLine(digraph);
var dfs = new DepthFirstOrder(digraph);
Console.WriteLine(" v pre post");
Console.WriteLine("--------------");
for (var vi = 0; vi < digraph.V; vi++)
{
Console.Write($"{vi} {dfs.Pre(vi)} {dfs.Post(vi)}{Environment.NewLine}");
}
Console.Write("Preorder: ");
foreach (int vi in dfs.Pre())
{
Console.Write($"{vi} ");
}
Console.WriteLine();
Console.Write("Postorder: ");
foreach (int vi in dfs.Post())
{
Console.Write($"{vi} ");
}
Console.WriteLine();
Console.Write("Reverse postorder: ");
foreach (int vi in dfs.ReversePost())
{
Console.Write($"{vi} ");
}
Console.ReadLine();
}
