public (IList <Vertex> Path, TWeight Cost) ShortestPath(Vertex start, Vertex end)
{
var untraveled = new HashSet <Vertex>();
var distances = new Dictionary <Vertex, WeightWrapper>();
var previous = new Dictionary <Vertex, Vertex>();
foreach (var v in Vertices.Cast <Vertex>())
{
distances[v] = WeightWrapper.Infinite;
previous[v] = null;
untraveled.Add(v);
}
distances[start] = WeightWrapper.For(default);
