/// <summary>
/// Специальный метод приводящий к куче
/// </summary>
/// <param name="i"></param>
public void heapify(int i)
{
int leftChild;
int rightChild;
int smallestChild;
for (; ;)
{
leftChild = 2 * i + 1;
rightChild = 2 * i + 2;
smallestChild = i;
if (leftChild < Size && list[leftChild].Key < list[smallestChild].Key)
{
smallestChild = leftChild;
}
if (rightChild < Size && list[rightChild].Key < list[smallestChild].Key)
{
smallestChild = rightChild;
}
if (smallestChild == i)
{
break;
}
HeapNode <T> temp = list[i];
list[i] = list[smallestChild];
list[smallestChild] = temp;
i = smallestChild;
}
}
/// <summary>
/// выдает минимальный элемент кучи и удаляет его
/// </summary>
/// <returns></returns>
public HeapNode <T> GetMin()
{
HeapNode <T> result = list[0];
list[0] = list[Size - 1];
list.RemoveAt(Size - 1);
heapify(0);
return(result);
}
/// <summary>
/// Добавить объект в кучу
/// </summary>
/// <param name="key">ключ</param>
/// <param name="value">значение</param>
public void Add(double key, T value)
{
list.Add(new HeapNode <T>(key, value));
int i = Size - 1;
int parent = (i - 1) / 2;
while (i > 0 && list[parent].Key > list[i].Key)
{
HeapNode <T> temp = list[i];
list[i] = list[parent];
list[parent] = temp;
//
i = parent;
parent = (i - 1) / 2;
}
}
public void DecreaseOrAdd(double key, T o)
{
HeapNode <T> kv = list.Find((KV) => { return(KV.Value.Equals(o)); });
if (kv != null)
{
int i = list.IndexOf(kv);
if (kv.Key > key)
{
kv.Key = key;
}
while (i > 1 && list[i / 2].Key > list[i].Key)
{
HeapNode <T> temp = list[i];
list[i] = list[i / 2];
list[i / 2] = temp;
}
}
else
{
Add(key, o);
}
}
Dictionary <Node, double> GetDistancesWithHeap(Node Start)
{
Dictionary <Node, double> Distances = new Dictionary <Node, double>();
List <Node> Closed = new List <Node>();
heap.Add(0, Start);
while (heap.Size > 0)
{
HeapNode <Node> KV = heap.GetMin();
Node Cur = KV.Value;
double CurPrior = KV.Key;
foreach (Link l in Cur.Links)
{
if (!Closed.Contains(l.To) && l.To != Cur)
{
heap.DecreaseOrAdd(CurPrior + l.Weight, l.To);
}
}
Closed.Add(Cur);
Distances.Add(Cur, CurPrior);
}
return(Distances);
}
