//Methods whos primary purpose is to assist other methods
public Edge firstBackTrackEdge(Graph g, List <Edge> path)
{
Edge lastMove = path[path.Count - 1];
path.Remove(lastMove);
g.addBackEdgeSet(lastMove);
g.addBackOtherEdges(lastMove.vertexTwo(), lastMove, coveredVertices(path));
g.addBackVertex(lastMove.vertexTwo());
Edge chosenEdge = selectShortestEdge(g, lastMove.vertexOne());
while (chosenEdge == null)
{
lastMove = path[path.Count - 1];
path.Remove(lastMove);
g.addBackEdgeSet(lastMove);
g.addBackVertex(lastMove.vertexTwo());
chosenEdge = selectShortestEdge(g, lastMove.vertexOne());
g.addBackOtherEdges(lastMove.vertexTwo(), lastMove, coveredVertices(path));
}
return(chosenEdge);
}
public Edge selectEdge(List <Edge> edgeList, int index)
{
Edge e = edgeList[index];
removeEdges(edgeList);
removeVertex(e.vertexOne());
removeVertex(e.vertexTwo());
return(e);
}
public string GeneralAlgorithm(Graph g)
{
DateTime start = DateTime.Now;
Graph gCopy = g.Copy();
bool backTrack = false;
List <Edge> path = new List <Edge>();
Edge startEdge = selectShortestEdge(gCopy, 1);
justRemovedEdge = startEdge;
path.Add(startEdge);
gCopy.removeEdges(gCopy.listEdges(1));
gCopy.removeVertex(justRemovedEdge.vertexOne());
gCopy.removeVertex(justRemovedEdge.vertexTwo());
gCopy.removeEdge(startEdge);
while (gCopy.numberOfVerticesRemaining() > 0)
{
Edge chosenEdge = null;
if (!backTrack)
{
chosenEdge = selectShortestEdge(gCopy, justRemovedEdge.vertexTwo());
}
else
{
chosenEdge = firstBackTrackEdge(gCopy, path);
if (path.Count > 0)
{
justRemovedEdge = path[path.Count - 1];
}
}
if (chosenEdge != null)
{
path.Add(chosenEdge);
gCopy.removeEdges(gCopy.listEdges(justRemovedEdge.vertexTwo()));
gCopy.removeVertex(chosenEdge.vertexOne());
gCopy.removeVertex(chosenEdge.vertexTwo());
gCopy.removeEdge(chosenEdge);
justRemovedEdge = chosenEdge;
backTrack = false;
}
else if (gCopy.numberOfVerticesRemaining() > 0)
{
backTrack = true;
}
}
DateTime stop = DateTime.Now;
TimeSpan timeDiff = (stop - start);
string outputString = String.Format("Time Taken: {0}:{1}:{2}:{3}\n", timeDiff.Days, timeDiff.Hours, timeDiff.Minutes, timeDiff.Seconds) + "Path: " + printEdges(path) + "\nDistance: " + pathDistance(path);
return(outputString);
}
