/// <summary>
/// Returns the shortest paths
/// </summary>
/// <param name="u">generic string</param>
/// <param name="v">generic string</param>
/// <param name="map">DirectedGraph map</param>
/// <param name="paths">Dictionary paths</param>
/// <returns></returns>
private decimal ShortestPath(string u, string v, DirectedGraph <string, decimal> map, out Dictionary <string, string> paths)
{
paths = new Dictionary <string, string>();
MinPriorityQueue <decimal, Edge <string, decimal> > tempQueue = new MinPriorityQueue <decimal, Edge <string, decimal> >();
paths.Add(u, u);
if (u.Equals(v))
{
return(0);
}
foreach (Edge <string, decimal> outGoEdge in map.OutgoingEdges(u))
{
tempQueue.Add(outGoEdge.Data, outGoEdge);
}
while (tempQueue.Count > 0) //possibly wrong
{
decimal p = tempQueue.MinimumPriority;
Edge <string, decimal> edgeRemoved = tempQueue.RemoveMinimumPriority();
if (!paths.ContainsKey(edgeRemoved.Destination))
{
paths.Add(edgeRemoved.Destination, edgeRemoved.Source);
if (edgeRemoved.Destination.Equals(v))
{
return(p);
}
foreach (Edge <string, decimal> outGoEdge in map.OutgoingEdges(edgeRemoved.Destination))
{
tempQueue.Add(p + outGoEdge.Data, outGoEdge);
}
}
}
return(-1);
}
/// <summary>
/// Finds a shortest path from the given start node to the given end node in the given graph.
/// </summary>
/// <param name="u">The start node.</param>
/// <param name="v">The end node.</param>
/// <param name="map">The graph.</param>
/// <param name="paths">The resulting shortest paths.</param>
/// <returns>The length of the shortest path.</returns>
private decimal ShortestPath(string u, string v, DirectedGraph <string, decimal> map,
out Dictionary <string, string> paths)
{
paths = new Dictionary <string, string>();
MinPriorityQueue <decimal, Edge <string, decimal> > pq = new MinPriorityQueue <decimal, Edge <string, decimal> >();
paths.Add(u, u);
if (u == v)
{
return(0);
}
foreach (Edge <string, decimal> e in map.OutgoingEdges(u))
{
pq.Add(e, e.Data);
}
while (pq.Count > 0)
{
decimal p = pq.MininumPriority;
Edge <string, decimal> e = pq.RemoveMinimumPriority();
if (!paths.ContainsKey(e.Destination))
{
paths.Add(e.Destination, e.Source);
if (e.Destination == v)
{
return(p);
}
foreach (Edge <string, decimal> outgoing in map.OutgoingEdges(e.Destination))
{
pq.Add(outgoing, p + outgoing.Data);
}
}
}
return(-1);
}
/// <summary>
/// Computes the shortest path from u to v in the map.
/// </summary>
/// <param name="u"></param>
/// <param name="v"></param>
/// <param name="map"></param>
/// <param name="paths"></param>
/// <returns></returns>
private decimal ShortestPath(string u, string v, DirectedGraph <string, decimal> map, out Dictionary <string, string> paths)
{
paths = new Dictionary <string, string>();
MinPriorityQueue <decimal, Edge <string, decimal> > queue = new MinPriorityQueue <decimal, Edge <string, decimal> >();
paths.Add(u, u);
if (u.Equals(v))
{
return(0);
}
foreach (Edge <string, decimal> i in map.OutgoingEdges(u))
{
queue.Add(i.Data, i);
}
while (queue.Count > 0)
{
decimal priority = queue.MinimumPriority;
Edge <string, decimal> temp = queue.RemoveMinimumPriority();
if (!paths.ContainsKey(temp.Destination))
{
paths.Add(temp.Destination, temp.Source);
if (temp.Destination == v)
{
return(priority);
}
foreach (Edge <string, decimal> i in map.OutgoingEdges(temp.Destination))
{
queue.Add(priority + i.Data, i);
}
}
}
return(-1);
}
/// <summary>
/// Finds a shortest path from the given start node to the given end node in the given graph.
/// </summary>
/// <param name="u">The start node.</param>
/// <param name="v">The end node.</param>
/// <param name="map">The graph.</param>
/// <param name="paths">The resulting shortest paths.</param>
/// <returns>The length of the shortest path.</returns>
private decimal ShortestPath(string u, string v, DirectedGraph <string, decimal> map, out Dictionary <string, string> paths)
{
//throw new NotImplementedException();
paths = new Dictionary <string, string>();
paths.Add(u, u);
if (u == v)
{
return(0);
}
MinPriorityQueue <decimal, Tuple <string, string> > q = new MinPriorityQueue <decimal, Tuple <string, string> >();
//add all outgoing edges from u
foreach (Tuple <string, decimal> edge in map.OutgoingEdges(u))
{
//add this edge to priority queue
q.Add(new Tuple <string, string>(u, edge.Item1), edge.Item2);
}
while (q.Count != 0)
{
decimal priority = q.MininumPriority;
Tuple <string, string> edge = q.RemoveMinimumPriority();
string x = edge.Item1;
string w = edge.Item2;
if (!paths.ContainsKey(w))
{
paths.Add(w, x);
if (w == v)
{
return(priority);
}
else
{
foreach (Tuple <string, decimal> edge2 in map.OutgoingEdges(w))
{
q.Add(new Tuple <string, string>(w, edge2.Item1), edge2.Item2 + priority);
}
}
}
}
return(-1);
}
/// <summary>
/// Finds a shortest path from the given start node to the given end node in the given graph.
/// </summary>
/// <param name="u">The start node.</param>
/// <param name="v">The end node.</param>
/// <param name="map">The graph.</param>
/// <param name="paths">The resulting shortest paths.</param>
/// <returns>The length of the shortest path.</returns>
private decimal ShortestPath(string u, string v, DirectedGraph <string, decimal> map,
out Dictionary <string, string> paths)
{
paths = new Dictionary <string, string>();
MinPriorityQueue <decimal, Tuple <string, string> > q = new MinPriorityQueue <decimal, Tuple <string, string> >();
paths.Add(u, u);
if (u == v)
{
return(0);
}
foreach (Tuple <string, decimal> t in map.OutgoingEdges(u))
{
string w = t.Item1;
decimal len = t.Item2;
q.Add(new Tuple <string, string>(u, w), len);
}
while (q.Count != 0)
{
decimal p = q.MininumPriority;
Tuple <string, string> edge = q.RemoveMinimumPriority();
string w = edge.Item1;
string x = edge.Item2;
if (!paths.ContainsKey(x))
{
paths.Add(x, w);
if (x == v)
{
return(p);
}
foreach (Tuple <string, decimal> t in map.OutgoingEdges(x))
{
string y = t.Item1;
decimal len = t.Item2;
q.Add(new Tuple <string, string>(x, y), p + len);
}
}
}
return(-1);
}
/// <summary>
/// Uses Dijkstra's Algorithm to find the shortest distance in a graph between point u and v!
/// </summary>
/// <param name="u"> Name of the node we are starting at </param>
/// <param name="v">Name of the node that serves as our destination </param>
/// <param name="map"> Map that we are sifting through to find the shortest path </param>
/// <param name="paths"> Dictionary whose keys are a node, and the value is it's previous node </param>
/// <returns> The shortest path in decimal form! </returns>
private static decimal ShortestPath(string u, string v, DirectedGraph <string, decimal> map, out Dictionary <string, string> paths)
{
paths = new Dictionary <string, string>();
// String value in Edge is a node that has already been visited!
// Priority is the shortest path up until the source node (string value in Edge)
MinPriorityQueue <decimal, Edge <string, decimal> > queue = new MinPriorityQueue <decimal, Edge <string, decimal> >();
paths.Add(u, u);
if (u == v)
{
return(0);
}
foreach (Edge <string, decimal> edge in map.OutgoingEdges(u))
{
queue.Add(edge.Data, edge);
}
while (queue.Count != 0)
{
decimal minPriority = queue.MinimumPriority;
Edge <string, decimal> nextEdge = queue.RemoveMinimumPriority();
if (paths.ContainsKey(nextEdge.Destination) == false)
{
paths.Add(nextEdge.Destination, nextEdge.Source);
if (nextEdge.Destination == v)
{
return(minPriority);
}
foreach (Edge <string, decimal> edge in map.OutgoingEdges(nextEdge.Destination))
{
//queue.Add(edge.Data, edge);
queue.Add(minPriority + edge.Data, edge);
}
}
}
return(-1);
}