private static void JohnsonFunction()
{
string filename = @"data\SimpleGraph.txt";
Graph <int> g = new Graph <int>();
//LoadGraph loader = new LoadGraph(g, @"data\GraphWithNoNegativeCycle.txt");
LoadGraph loader = new LoadGraph();
loader.LoadAdjacencyListGraph(g, filename);
var alg = new GraphTraversal();
var result = alg.JohnsonFunction(g);
if (result.Item1)
{
Console.WriteLine("Negative Path found");
return;
}
if (result.Item2 != null)
{
foreach (var item in result.Item2)
{
Tuple <GraphNode <int>, GraphNode <int> > keyset = item.Key;
GraphNode <int> nodeFrom = keyset.Item1;
GraphNode <int> nodeTo = keyset.Item2;
Console.WriteLine("Shortest distance from Node: " + nodeFrom.Value + " To: " + nodeTo.Value + " = " + item.Value);
}
}
Console.WriteLine("Path found: ");
}
static void BellmanFordTestMethod()
{
Graph <int> g = new Graph <int>();
LoadGraph loader = new LoadGraph();
loader.LoadAdjacencyListGraph(g, @"data\SimpleGraph.txt");
GraphNode <int> start = g.GetVertex(new GraphNode <int>(1));
var alg = new GraphTraversal();
var result = alg.BellmanFordFunction(g, start);
Console.WriteLine("Negative Cycle found: " + result.Item1);
}
private static void FloydWarshallFunction()
{
string filename = @"data\GraphWithNegativeCycle.txt";
Graph <int> g = new Graph <int>();
//LoadGraph loader = new LoadGraph(g, @"data\SimpleGraphWithNegativeWeights.txt");
LoadGraph loader = new LoadGraph();
loader.LoadAdjacencyListGraph(g, filename);
var alg = new GraphTraversal();
Stopwatch sw = new Stopwatch();
sw.Start();
var result = alg.FloydWarshallFunction(g);
sw.Stop();
if (result.Item1)
{
Console.WriteLine("Negative cycle exists");
return;
}
double minVal = double.MaxValue;
if (result.Item2 != null)
{
foreach (var item in result.Item2)
{
Tuple <GraphNode <int>, GraphNode <int> > keyset = item.Key;
GraphNode <int> nodeFrom = keyset.Item1;
GraphNode <int> nodeTo = keyset.Item2;
Console.WriteLine("Shortest distance from Node: " + nodeFrom.Value + " To: " + nodeTo.Value + " = " + item.Value);
if (minVal > item.Value)
{
minVal = item.Value;
}
Console.WriteLine("The minimum cost is " + minVal);
}
}
else
{
Console.WriteLine("This graph has a negative cycle");
}
Console.WriteLine("Path found: Elapsed time(ms) : " + sw.ElapsedMilliseconds);
}