static void TestCase4()
{
var random = new Random();
var myHeap = new FibonacciHeap<double>(int.MinValue, Comparer<double>.Default);
var thirdPartyHeap = new FastPriorityQueue<FastPriorityQueueNode>(1000);
for (var i = 0; i < 1000; i++)
{
if (random.Next(3) == 0 && thirdPartyHeap.Any())
{
var myResult = myHeap.ExtractMin();
var otherResult = thirdPartyHeap.Dequeue();
Assert(myResult.Item1);
Assert(Math.Abs(myResult.Item2 - otherResult.Priority) < double.Epsilon);
}
else
{
var value = random.NextDouble()*10;
myHeap.Insert(value);
thirdPartyHeap.Enqueue(new FastPriorityQueueNode(), value);
}
}
while (thirdPartyHeap.Any())
{
var myResult = myHeap.ExtractMin();
var otherResult = thirdPartyHeap.Dequeue();
Assert(myResult.Item1);
Assert(Math.Abs(myResult.Item2 - otherResult.Priority) < double.Epsilon);
}
}
public static int Dijkstra(Vertex from, Vertex to, Graph graph)
{
HashSet<Vertex> visited = new HashSet<Vertex>();
Dictionary<Vertex, FibonacciHeap<int, Vertex>.Node> nodes = new Dictionary<Vertex, FibonacciHeap<int, Vertex>.Node>();
FibonacciHeap<int, Vertex> labels = new FibonacciHeap<int, Vertex>();
// Initialize labels.
foreach (var vertex in graph.Vertices)
{
var n = labels.Add(vertex == from ? 0 : int.MaxValue, vertex);
nodes.Add(vertex, n);
}
int currentLabel = int.MaxValue;
while (!visited.Contains(to))
{
var currentNode = labels.ExtractMin();
var current = currentNode.Value;
currentLabel = currentNode.Key;
// Consider all edges ending in unvisited neighbours
var edges =
graph.GetEdgesForVertex(current).Where(x => !visited.Contains(x.Other(current)));
// Update labels on the other end.
foreach (var edge in edges)
{
if (currentNode.Key + edge.Cost < nodes[edge.Other(current)].Key)
labels.DecreaseKey(nodes[edge.Other(current)], currentNode.Key + edge.Cost);
}
visited.Add(current);
}
return currentLabel;
}
public IList <ILevelTile> CalculatePath(ILevelTile from, ILevelTile to)
{
target = to;
openNodes = new FibonacciHeap <float>();
closedNodes = new HashSet <AStarNode>();
tilesToNodes = new Dictionary <ILevelTile, AStarNode>();
AStarNode startNode = new AStarNode(from, heuristic.GetDistance(from.CenterPos, to.CenterPos));
startNode.cost = 0;
tilesToNodes.Add(from, startNode);
openNodes.Insert(startNode);
do
{
AStarNode currNode = (AStarNode)openNodes.ExtractMin();
if (currNode.tile.Equals(to))
{
return(GetPathToNode(currNode));
}
closedNodes.Add(currNode);
ExpandNode(currNode);
} while (openNodes.IsEmpty() == false);
// No path found
return(null);
}
public void ConsolidatedHeapExtractMin_CorrectConsolidation()
{
// Create consolidated heap
FibonacciHeap <int> heap = new FibonacciHeap <int>();
IList <int> input = new List <int>()
{
0,
28,
-13,
80,
3,
7,
-7,
42,
-11,
12
};
IList <int> expectedElementOrder = new List <int>()
{
7,
42,
12,
28,
80,
3,
0,
-7
};
foreach (int value in input)
{
heap.Insert(value);
}
heap.ExtractMin();
// Trigger second consolidation
heap.ExtractMin();
IList <int> result = heap.GetAllValues();
for (int i = 0; i < expectedElementOrder.Count; ++i)
{
NUnit.Framework.Assert.IsTrue(expectedElementOrder[i] == result[i]);
}
NUnit.Framework.Assert.IsTrue(heap.GetMin() == -7);
}
public void ConsolidatedHeapDecreaseKey_CorrectCuts()
{
FibonacciHeap <int> heap = new FibonacciHeap <int>();
IList <FibonacciNode <int> > input = new List <FibonacciNode <int> >()
{
new FibonacciNode <int>(0),
new FibonacciNode <int>(28),
new FibonacciNode <int>(-13),
new FibonacciNode <int>(80),
new FibonacciNode <int>(3),
new FibonacciNode <int>(7),
new FibonacciNode <int>(-7),
new FibonacciNode <int>(42),
new FibonacciNode <int>(-11),
new FibonacciNode <int>(12)
};
IList <int> expectedElementOrder = new List <int>()
{
7,
-8,
-11,
12,
-42,
80,
-1,
-3,
0
};
foreach (FibonacciNode <int> value in input)
{
heap.Insert(value);
}
heap.ExtractMin();
// A decrease key with no structural changes
heap.DecreaseKey(input[6], -8);
// Normal cuts with parent marked
heap.DecreaseKey(input[7], -42);
heap.DecreaseKey(input[4], -1);
// Double cascading cut
heap.DecreaseKey(input[1], -3);
IList <int> result = heap.GetAllValues();
for (int i = 0; i < expectedElementOrder.Count; ++i)
{
NUnit.Framework.Assert.IsTrue(expectedElementOrder[i] == result[i]);
}
NUnit.Framework.Assert.IsTrue(heap.GetMin() == -42);
}
public static Path DijkstraPath(Vertex from, Vertex to, Graph graph)
{
HashSet<Vertex> visited = new HashSet<Vertex>();
Dictionary<Vertex, FibonacciHeap<int, Vertex>.Node> nodes =
new Dictionary<Vertex, FibonacciHeap<int, Vertex>.Node>();
Dictionary<Vertex, Edge> comingFrom = new Dictionary<Vertex, Edge>();
FibonacciHeap<int, Vertex> labels = new FibonacciHeap<int, Vertex>();
// Initialize labels.
foreach (var vertex in graph.Vertices)
{
var n = labels.Add(vertex == from ? 0 : int.MaxValue, vertex);
nodes.Add(vertex, n);
comingFrom.Add(vertex, null);
}
while (!visited.Contains(to))
{
var currentNode = labels.ExtractMin();
var current = currentNode.Value;
// Consider all edges ending in unvisited neighbours
var edges =
graph.GetEdgesForVertex(current).Where(x => !visited.Contains(x.Other(current)));
// Update labels on the other end.
foreach (var edge in edges)
{
if (currentNode.Key + edge.Cost < nodes[edge.Other(current)].Key)
{
labels.DecreaseKey(nodes[edge.Other(current)], currentNode.Key + edge.Cost);
comingFrom[edge.Other(current)] = edge;
}
}
visited.Add(current);
}
// Now travel back, to find the actual path
List<Edge> pathEdges = new List<Edge>();
Vertex pathVertex = to;
while (pathVertex != from)
{
pathEdges.Add(comingFrom[pathVertex]);
pathVertex = comingFrom[pathVertex].Other(pathVertex);
}
pathEdges.Reverse();
Path path = new Path(from);
path.Edges.AddRange(pathEdges);
return path;
}
public void UnconsolidatedHeapExtractMin_CorrectValue()
{
FibonacciNode <int> node = new FibonacciNode <int>(-20);
FibonacciHeap <int> heap = new FibonacciHeap <int>();
IList <int> input = new List <int>()
{
0,
28,
-13,
80
};
heap.Insert(node);
foreach (int value in input)
{
heap.Insert(value);
}
NUnit.Framework.Assert.IsTrue(heap.ExtractMin() == node);
NUnit.Framework.Assert.IsTrue(heap.GetMin() == -13);
NUnit.Framework.Assert.IsTrue(heap.GetAllValues().Count == input.Count);
}
public void EmptyHeapExtractMin_ReturnsNull()
{
FibonacciHeap <int> heap = new FibonacciHeap <int>();
NUnit.Framework.Assert.Null(heap.ExtractMin());
}
public static Dictionary<Vertex, Path> DijkstraPathToAll(Vertex from, Graph graph, bool onlyTerminals)
{
Dictionary<Vertex, Edge> comingFrom = new Dictionary<Vertex, Edge>();
HashSet<Vertex> visited = new HashSet<Vertex>();
Dictionary<Vertex, FibonacciHeap<int, Vertex>.Node> nodes =
new Dictionary<Vertex, FibonacciHeap<int, Vertex>.Node>();
Dictionary<Vertex, Path> paths = new Dictionary<Vertex, Path>();
FibonacciHeap<int, Vertex> labels = new FibonacciHeap<int, Vertex>();
// Initialize labels.
foreach (var vertex in graph.Vertices)
{
var n = labels.Add(vertex == from ? 0 : int.MaxValue, vertex);
nodes.Add(vertex, n);
}
while (paths.Count < (onlyTerminals ? graph.Terminals.Count - 1 : graph.NumberOfVertices - 1))
{
var currentNode = labels.ExtractMin();
var current = currentNode.Value;
// Consider all edges ending in unvisited neighbours
var edges =
graph.GetEdgesForVertex(current).Where(x => !visited.Contains(x.Other(current)));
// Update labels on the other end.
foreach (var edge in edges)
{
if (currentNode.Key + edge.Cost < nodes[edge.Other(current)].Key)
{
labels.DecreaseKey(nodes[edge.Other(current)], currentNode.Key + edge.Cost);
comingFrom[edge.Other(current)] = edge;
}
}
visited.Add(current);
if (current != from && (!onlyTerminals || graph.Terminals.Contains(current)))
{
// Travel back the path
List<Edge> pathEdges = new List<Edge>();
Vertex pathVertex = current;
while (pathVertex != from)
{
pathEdges.Add(comingFrom[pathVertex]);
pathVertex = comingFrom[pathVertex].Other(pathVertex);
}
pathEdges.Reverse();
Path path = new Path(from);
path.Edges.AddRange(pathEdges);
paths[current] = path;
}
}
return paths;
}
public static List<Path> NearestTerminals(Vertex from, Graph graph, int n)
{
List<Path> foundPaths = new List<Path>();
HashSet<Vertex> visited = new HashSet<Vertex>();
Dictionary<Vertex, FibonacciHeap<int, Vertex>.Node> nodes = new Dictionary<Vertex, FibonacciHeap<int, Vertex>.Node>();
FibonacciHeap<int, Vertex> labels = new FibonacciHeap<int, Vertex>();
Dictionary<Vertex, Edge> comingFrom = new Dictionary<Vertex, Edge>();
if (graph.Terminals.Contains(from))
foundPaths.Add(new Path(from));
// Initialize labels.
foreach (var vertex in graph.Vertices)
{
var node = labels.Add(vertex == from ? 0 : int.MaxValue, vertex);
nodes.Add(vertex, node);
comingFrom.Add(vertex, null);
}
while (!labels.IsEmpty() && foundPaths.Count < n)
{
var currentNode = labels.ExtractMin();
var current = currentNode.Value;
// Consider all edges ending in unvisited neighbours
var edges =
graph.GetEdgesForVertex(current).Where(x => !visited.Contains(x.Other(current)));
// Update labels on the other end.
foreach (var edge in edges)
{
if (currentNode.Key + edge.Cost < nodes[edge.Other(current)].Key)
{
labels.DecreaseKey(nodes[edge.Other(current)], currentNode.Key + edge.Cost);
comingFrom[edge.Other(current)] = edge;
}
}
visited.Add(current);
if (graph.Terminals.Contains(current) && current != from)
{
// Now travel back, to find the actual path
List<Edge> pathEdges = new List<Edge>();
Vertex pathVertex = current;
while (pathVertex != from)
{
pathEdges.Add(comingFrom[pathVertex]);
pathVertex = comingFrom[pathVertex].Other(pathVertex);
}
pathEdges.Reverse();
Path path = new Path(from);
path.Edges.AddRange(pathEdges);
foundPaths.Add(path);
}
}
return foundPaths;
}
