private static Graph ReadFromFile(string fileName)
{
//The format of line is:
// Id: id_neighbour_1, id_neighbour_2, ... , id_nieghbour_n
var g = new Graph();
var allLines = File.ReadAllLines(fileName);
var splittedAllLines = allLines.Select(x => x.Split(':'));
if (splittedAllLines.Any(x => x.Count() != 2))
throw new InvalidFileFormatException();
foreach (var id in splittedAllLines.Select(x => x[0]))
{
g.AddVertex(ParseVertexId(id));
}
foreach (var line in splittedAllLines)
{
var fromId = ParseVertexId(line[0]);
var neighbours = line[1].Split(',');
foreach (var neighbour in neighbours)
{
int toId = ParseVertexId(neighbour);
if(!g.ContainsVertex(toId))
throw new InvalidFileFormatException();
g.AddDirectedEdge(fromId, toId);
}
}
return g;
}
public Graph Shrink(int n, int m)
{
var h = new Graph();
foreach (var v in AllVerticies.Where(x => x.Id != m))
{
h.AddVertex(v.Id);
}
foreach (var vertex in AllVerticies.Where(x => x.Id != m))
{
foreach (var neighbour in vertex.AllNeighbours.Where(x => x.Id != m))
{
h.AddDirectedEdge(vertex.Id, neighbour.Id);
}
}
var mVertex = verticies[m];
foreach (var neighbourOfM in mVertex.AllNeighbours.Where(x => x.Id != n))
{
h.AddUndirectedEdge(n, neighbourOfM.Id);
}
return h;
}
