public void Contract(Edge edge)
{
var toRemove =
Edges.Where(
e =>
e == edge || (e.Left == edge.Left && e.Right == edge.Right) ||
(e.Left == edge.Right && e.Right == edge.Left)).ToArray();
foreach (var item in toRemove) Edges.Remove(item);
Nodes.Remove(edge.Right);
var toMove = Edges.Where(e => e.Left == edge.Right || e.Right == edge.Right);
foreach (var item in toMove)
{
if (item.Right == edge.Right) item.Right = edge.Left;
else item.Left = edge.Left;
}
}
public void Contract(Edge edge)
{
throw new System.NotImplementedException();
}