protected static internal void DijkstraMinPath(string sourceID, string destinationID)
{
try
{
var watch = Stopwatch.StartNew();
var priotityQueue = new Queue <NextAirport>();
List <string> visited = new List <string>();
var path = new Dictionary <NextAirport, NextAirport>();
Airport source = AirlineData.GetAirPort(sourceID);
var next = AirlineData.GetNextStation(sourceID);
next.Weight = 0;//sorce
priotityQueue.Enqueue(next);
Graph.Source = next;
double BestPrice = 0;
path[next] = null;
while (priotityQueue.Count > 0)
{
var _flight = priotityQueue.Dequeue();
if (_flight.Current.ID == destinationID)
{
watch.Stop();
Graph.Destination = _flight;
Graph.Path = path;
Console.WriteLine("Time spended {0}", watch.ElapsedMilliseconds);
Console.WriteLine("Count of visited vertices = {0}", visited.Count);
ReturnMinPath();
return;
}
visited.Add(_flight.Current.ID);
foreach (var neighbour in _flight.adjacementList)
{
NextAirport _next = AirlineData.GetNextStation(neighbour.DestinationId);;
if (!visited.Contains(neighbour.DestinationId) && _next != null)
{
var best = GetPriceByPath(_flight.Current.ID, neighbour.DestinationId) + _flight.Weight;//maybe best price
if (best < _next.Weight)
{
_next.Weight = best;
priotityQueue.Enqueue(_next);
path[_next] = _flight;
SortQueue(ref priotityQueue);
}
}
}
}
Console.ReadKey();
}
catch (Exception r)
{
Console.WriteLine(r);
}
}
protected internal static NextAirport GetNextStation(string stationID)
{
Airport curr = GetAirPort(stationID);
if (curr != null)
{
NextAirport nextAirport = new NextAirport(curr, curr.AirportName, int.MaxValue, curr.routes);
return(nextAirport);
}
else
{
return(null);
}
}
protected static internal List <NextAirport> ReturnMinPath(NextAirport pathNode) // відновлення шляху після алгоритму А*
{
List <NextAirport> result = new List <NextAirport>();
var currentNode = pathNode;
Console.WriteLine(currentNode.PathLengthFromStart);
result.Add(pathNode);
while (currentNode != null)
{
result.Add(currentNode.previous);
currentNode = currentNode.previous;
}
result.Reverse();
result.RemoveAt(0);
foreach (var x in result)
{
Console.Write($" {x.Current.ID} ->>>");
}
Console.WriteLine();
return(result);
}
protected static internal List <NextAirport> AStarMinPath(string sourceID, string destinationID)
{
// отримуємо найкоротший шлях від аеропорта А до аеропорта Б
NextAirport neighbourNode1;
var watch = Stopwatch.StartNew();
var closedSet = new Queue <NextAirport>();
var openSet = new Queue <NextAirport>();
AStar.Source = AirlineData.GetNextStation(sourceID);
AStar.Destination = AirlineData.GetNextStation(destinationID);
AStar.Source.previous = null;
AStar.Source.PathLengthFromStart = 0;
AStar.Source.HeuristicEstimatePathLength = GetPath(AStar.Source.Current, AStar.Destination.Current);
openSet.Enqueue(AStar.Source);
// Console.WriteLine($"Start searching path from {AStar.Source.Current.AirportName} to {AStar.Destination.Current.AirportName} ");
while (openSet.Count > 0)
{
var currentAirport = openSet.OrderBy(node => node.EstimateFullPathLength).First();
currentAirport = openSet.Dequeue();
if (currentAirport.Current.ID == destinationID) // mccarran
{
Console.WriteLine("Time spended {0}", watch.ElapsedMilliseconds);
Console.WriteLine($"There is the way from {AStar.Source.Current.AirportName} to {AStar.Destination.Current.AirportName} ");
return(ReturnMinPath(currentAirport));
}
closedSet.Enqueue(currentAirport);
foreach (var neighbourAirport in currentAirport.adjacementList)
{
neighbourNode1 = AirlineData.GetNextStation(neighbourAirport.DestinationId);
if (closedSet.Count(node => node.Current.ID == neighbourNode1.Current.ID) > 0)
{
continue;
}
double temp_PathLenghtFromStart = currentAirport.PathLengthFromStart + GetPath(currentAirport.Current, neighbourNode1.Current); // neighbourNode1.PathLengthFromStart = currentAirport.PathLengthFromStart + GetPath(currentAirport.Current, AirlineData.GetAirPort(neighbourNode.ITA)); // виглядає правильніше, працює довше, результат коректний
var openNode = openSet.FirstOrDefault(node => node.Current.ID == neighbourNode1.Current.ID);
if (openNode == null || temp_PathLenghtFromStart <= neighbourNode1.PathLengthFromStart)
{
neighbourNode1.previous = currentAirport;
neighbourNode1.PathLengthFromStart = temp_PathLenghtFromStart;
neighbourNode1.HeuristicEstimatePathLength = GetPath(neighbourNode1.Current, AStar.Destination.Current);
}
if (openNode == null)
{
openSet.Enqueue(neighbourNode1);
}
}
}
Console.WriteLine($"There is no way from airport with name {AStar.Source.Current.AirportName} to airport {AStar.Destination.Current.AirportName}");
Console.WriteLine("Time spended {0}", watch.ElapsedMilliseconds);
return(null);
}
