public void GetShortestPath(string start, Action <string, string, decimal> func = null)
{
Station vertexNode = Find(start);
Queue <Station> queue = new Queue <Station>();
InitVisited();
vertexNode.Visited = true;
queue.Enqueue(vertexNode);
while (queue.Count > 0)
{
Station curruntStation = queue.Dequeue();
Route route = curruntStation.FirstRoute;
//访问此顶点的所有邻接点
while (route != null)
{
var nextVertex = route.Station;
func?.Invoke(curruntStation.Name, route.GetDestinationStation(), route.Distance);
if (!nextVertex.Visited)
{
queue.Enqueue(nextVertex);
}
nextVertex.Visited = true;
//访问下一个邻接点
route = route.NextRoute;
}
}
}
private static void VerifyRoute(Station endStation, Route route)
{
if (route.GetDestinationStation().Equals(endStation.Name))
{
throw new ArgumentException("添加了重复的边！");
}
}
//使用递归进行深度优先遍历
private void DFS(Station startStation, Func <decimal, Stack <string>, bool> func = null, decimal weight = 0, Stack <string> stack = null)
{
startStation.Visited = true;
Route route = startStation.FirstRoute;
while (route != null)
{
weight += route.Distance;
stack?.Push(route.GetDestinationStation());
//外置条件是否继续遍历
var isdfs = func?.Invoke(weight, stack) ?? false;
var nextVertex = route.Station;
//如果邻接点未被访问，则递归访问它的边
if (!nextVertex.Visited || isdfs)
{
DFS(nextVertex, func, weight, stack);
}
stack.Pop();
weight -= route.Distance;
route = route.NextRoute;
}
}
