public void testToposort()
{
OrientedGraph og = oriented();
List <int> order = Toposort.TopologicalOrdering(og);
List <int> correct = new List <int>()
{
0, 6, 3, 2, 5, 4, 1
};
Assert.AreEqual(correct, order);
og.AddEdge(3, 1, 1);
order = Toposort.TopologicalOrdering(og);
Assert.AreEqual(new List <int>(), order);
}
/// <summary>
/// This is example program that reads CSV file containing dependencies
/// for installing different programs and outputs order in which
/// programs have to be installed so that no dependencies are missing
/// when programs are installed.
/// </summary>
public static void Main()
{
OrientedGraph og = new OrientedGraph();
// Read input data
string[] lines = System.IO.File.ReadAllLines("dependencies.csv");
// Assign index to every program (create pairing - name, index)
Dictionary <string, long> programs = new Dictionary <string, long>();
string [] names = new string[lines.Length];
int i = 0;
// Parse input, add vertices to graph and remember their indices
foreach (string line in lines)
{
string programName = line.Split(',')[0];
programs.Add(programName, i);
names[i] = programName;
og.AddVertex(i);
i++;
}
// Add edges to a graph
foreach (string line in lines)
{
string[] dependencies = line.Split(',');
for (int j = 1; j < dependencies.Length; j++)
{
long destination = programs[dependencies[j]];
long source = programs[dependencies[0]];
og.AddEdge(source, destination);
}
}
// Find topological ordering of dependencies
List <long> topoOrder = Toposort.TopologicalOrdering(ref og);
// Print order in which programs have to be installed
Console.WriteLine("Install in following order:");
for (int j = 0; j < topoOrder.Count; j++)
{
Console.Write(names[topoOrder[j]] + " ");
if (j + 1 < topoOrder.Count)
{
Console.Write("--> ");
}
}
Console.WriteLine();
}
