public ICollection <Way> RemoveDeadNodes()
{
var edges = GetEdges();
var deadWays = new HashSet <Way>();
var visited = new HashSet <long>();
var queue = new Queue <long>();
queue.Enqueue(Ways.First().Start);
while (queue.Any())
{
var node = queue.Dequeue();
foreach (var neighbour in edges[node])
{
if (visited.Contains(neighbour))
{
continue;
}
visited.Add(neighbour);
queue.Enqueue(neighbour);
}
}
foreach (var way in Ways.ToList())
{
if (visited.Contains(way.Start))
{
continue;
}
Ways.Remove(way);
deadWays.Add(way);
}
return(deadWays);
}