public void TwoValueTest()
{
PairingHeap <int> pairingHeap = new PairingHeap <int>((x, y) => x > y);
pairingHeap.Insert(10);
pairingHeap.Insert(-2);
var value = pairingHeap.ExtractMinimum();
Assert.Equal(-2, value.value);
value = pairingHeap.ExtractMinimum();
Assert.Equal(10, value.value);
}
public static (bool connected, Graph tree) Prim(this Graph g, int startingVertex = 0)
{
if (g.Directed)
{
throw new WrongGraphException("Graph must be an undirected graph");
}
if (startingVertex < 0 || startingVertex >= g.VerticesCount)
{
throw new ArgumentOutOfRangeException("startingVertex");
}
Graph tree = g.IsolatedGraph(g.Directed);
PairingHeap <Edge> queue = new PairingHeap <Edge>((x, y) => x.Weight > y.Weight);
UnionFind unionFind = new UnionFind(g.VerticesCount);
foreach (var e in g.GetEdgesFrom(startingVertex))
{
queue.Insert(e);
}
int c = 0;
while (true)
{
if (queue.IsEmpty() || c == g.VerticesCount - 1)
{
return(c == g.VerticesCount - 1 ? true : false, tree);
}
var e = queue.ExtractMinimum();
if (unionFind.FindParent(e.value.From) != unionFind.FindParent(e.value.To))
{
tree.AddEdge(e.value);
unionFind.Union(e.value.From, e.value.To);
foreach (var f in g.GetEdgesFrom(e.value.To))
{
queue.Insert(f);
}
c++;
}
}
}
public void NValueTest(int n)
{
PairingHeap <int> pairingHeap = new PairingHeap <int>((x, y) => x > y);
List <int> lista = new List <int>();
Random random = new Random();
for (int i = 0; i < n; i++)
{
int value = random.Next() % n * (0 == random.Next() % 2 ? -1 : 1);
lista.Add(value);
pairingHeap.Insert(value);
}
lista.Sort();
for (int i = 0; i < n; i++)
{
var value = pairingHeap.ExtractMinimum();
Assert.Equal(lista[i], value.value);
}
}
public static (bool connected, Graph tree) Kruskal(this Graph g)
{
if (g.Directed)
{
throw new WrongGraphException("Graph must be an undirected graph");
}
Graph tree = g.IsolatedGraph(g.Directed);
PairingHeap <Edge> queue = new PairingHeap <Edge>((x, y) => x.Weight > y.Weight);
UnionFind unionFind = new UnionFind(g.VerticesCount);
for (int i = 0; i < g.VerticesCount; i++)
{
foreach (var e in g.GetEdgesFrom(i))
{
queue.Insert(e);
}
}
int c = 0;
while (true)
{
if (queue.IsEmpty() || c == g.VerticesCount - 1)
{
return(c == g.VerticesCount - 1 ? true : false, tree);
}
var e = queue.ExtractMinimum();
if (unionFind.FindParent(e.value.From) != unionFind.FindParent(e.value.To))
{
tree.AddEdge(e.value);
unionFind.Union(e.value.From, e.value.To);
c++;
}
}
}
