private void DfsVisit(GraphBase g, int u, int p)
{
_marked[u] = true;
foreach (var v in g.Adj(u))
{
if (_hasCycle)
{
break;
}
if (!_marked[v])
{
_parents[v] = u;
DfsVisit(g, v, u);
}
else if (v != p)
{
_cycle = new Stack <int>();
_cycle.Push(v);
while (u != v)
{
_cycle.Push(u);
u = _parents[u];
}
_cycle.Push(v);
_hasCycle = true;
break;
}
}
}
private void DfsVisit(GraphBase g, int u, int p)
{
_vertices[u].Color = Color.Gray;
foreach (var v in g.Adj(u))
{
if (_hasCycle)
{
break;
}
if (_vertices[v].Color != Color.Gray)
{
_vertices[v].Parent = _vertices[u];
DfsVisit(g, v, u);
}
else if (v != p)
{
_cycle = new Stack <int>();
_cycle.Push(v);
while (u != v)
{
_cycle.Push(u);
u = _vertices[u].Parent.Val;
}
_cycle.Push(v);
_hasCycle = true;
break;
}
}
}
//------converters
public void Convert2anothertype()
{
GraphBase <VertexType, EdgeType> ng;// will conatain new graph referance;
if (g is MatrixBasedGraph <VertexType, EdgeType> )
{
ng = new ListBasedGraphSE <VertexType, EdgeType>(VertexCount, g.IsDirected);
}
else
{
ng = new MatrixBasedGraph <VertexType, EdgeType>(VertexCount, g.IsDirected);
}
//objectless functional calls are routed to g object
for (int i = 0; i < VertexCount; i++)
{
for (int j = 0; j < VertexCount; j++)
{
if (EdgeExists(i, j))
{
ng.AddEdge(i, j, GetEdgeWeight(i, j));
}
}
}
g = ng;
PrepareIterator(0);
}
public GraphController(int VertexCount, bool listbased, bool directed)
{
if (listbased)
{
g = new ListBasedGraphSE <VertexType, EdgeType>(VertexCount, directed);
}
else
{
g = new MatrixBasedGraph <VertexType, EdgeType>(VertexCount, directed);
}
PrepareIterator(0);
}
public Cycle1(GraphBase g)
{
_marked = new bool[g.V];
_parents = new int[g.V];
for (int i = 0; i < g.V; i++)
{
if (_hasCycle)
{
break;
}
if (!_marked[i])
{
DfsVisit(g, i, i);
}
}
}
public Cycle(GraphBase g)
{
_vertices = new Vertex[g.V];
for (int i = 0; i < g.V; i++)
{
_vertices[i] = new Vertex {
Color = Color.White, Val = i
};
}
for (int i = 0; i < g.V; i++)
{
if (_hasCycle)
{
break;
}
if (_vertices[i].Color == Color.White)
{
DfsVisit(g, i, i);
}
}
}
