/// <summary>
/// Computes a shortest paths tree from each vertex to to every other vertex in
/// the edge-weighted digraph <tt>G</tt>.
/// </summary>
/// <param name="g">G the edge-weighted digraph</param>
/// <exception cref="ArgumentException">if an edge weight is negative</exception>
/// <exception cref="ArgumentException">unless 0 <= <tt>s</tt> <= <tt>V</tt> - 1</exception>
public DijkstraAllPairsSP(EdgeWeightedDigraph g)
{
_all = new DijkstraSP[g.V];
for (var v = 0; v < g.V; v++)
{
_all[v] = new DijkstraSP(g, v);
}
}
public void Run()
{
Console.WriteLine("Choose file:"); // Prompt
Console.WriteLine("1 - tinyEWD.txt"); // Prompt
Console.WriteLine("2 - mediumEWD.txt"); // Prompt
//Console.WriteLine("3 - mediumEWG.txt"); // Prompt
Console.WriteLine("or quit"); // Prompt
var fileNumber = Console.ReadLine();
string fileName;
switch (fileNumber)
{
case "1":
fileName = "tinyEWD.txt";
break;
case "2":
fileName = "mediumEWD.txt";
break;
//case "3":
// fileName = "largeEWG.zip";
// break;
case "quit":
return;
default:
return;
}
var @in = new In($"Files\\Graphs\\{fileName}");
var lines = @in.ReadAllLines();
var lineIterator = 0;
var v = 0;
var e = 0;
var edges = new List<DirectedEdge>();
foreach (var line in lines)
{
if (lineIterator == 0)
{
v = Convert.ToInt32(line);
}
if (lineIterator == 1)
{
e = Convert.ToInt32(line);
}
if (lineIterator > 1)
{
var lineSplitted = line.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);
var ve = Convert.ToInt32(lineSplitted[0]);
var we = Convert.ToInt32(lineSplitted[1]);
var weight = Convert.ToDouble(lineSplitted[2], CultureInfo.InvariantCulture);
var edge = new DirectedEdge(ve, we, weight);
edges.Add(edge);
}
lineIterator++;
}
var edgeWeightedDigraph = new EdgeWeightedDigraph(v, e, edges);
Console.WriteLine(edgeWeightedDigraph);
const int s = 0;
// compute shortest paths
var sp = new DijkstraSP(edgeWeightedDigraph, s);
// print shortest path
for (var t = 0; t < edgeWeightedDigraph.V; t++)
{
if (sp.HasPathTo(t))
{
Console.Write($"{s} to {t} {$"{sp.DistTo(t):0.00}"} ");
foreach (var edge in sp.PathTo(t))
{
Console.Write($"{edge} ");
}
Console.WriteLine();
}
else
{
Console.WriteLine($"{s} to {t} no path{Environment.NewLine}");
}
}
Console.ReadLine();
}
/// <summary>
/// Computes a shortest paths tree from each vertex to to every other vertex in
/// the edge-weighted digraph <tt>G</tt>.
/// </summary>
/// <param name="g">G the edge-weighted digraph</param>
/// <exception cref="ArgumentException">if an edge weight is negative</exception>
/// <exception cref="ArgumentException">unless 0 <= <tt>s</tt> <= <tt>V</tt> - 1</exception>
public DijkstraAllPairsSP(EdgeWeightedDigraph g)
{
_all = new DijkstraSP[g.V];
for (var v = 0; v < g.V; v++)
_all[v] = new DijkstraSP(g, v);
}