private void SwapValue(BinaryHeapNode <T> a, BinaryHeapNode <T> b)
{
T temp = a.Value;
a.Value = b.Value;
b.Value = temp;
}
private void Sink(BinaryHeapNode <T> node)
{
if (node.LeftChild == null)
{
return;
}
if (node.RightChild == null)
{
if (node.Value.CompareTo(node.LeftChild.Value) > 0)
{
SwapValue(node, node.LeftChild);
Sink(node.LeftChild);
}
}
else
{
BinaryHeapNode <T> compareNode = node.LeftChild.Value.CompareTo(node.RightChild.Value) < 0 ? node.LeftChild : node.RightChild;
if (node.Value.CompareTo(compareNode.Value) > 0)
{
SwapValue(node, compareNode);
Sink(compareNode);
}
}
}
public BinaryHeap()
{
NodeList = new List <BinaryHeapNode <T> >();
//填充一个空位作为根节点的父节点(value=null),目的是后面在添加新节点时方便为新节点寻找父节点
//父节点index = 子节点index >> 1
BinaryHeapNode <T> baseNode = new BinaryHeapNode <T>()
{
Index = 0
};
Root = baseNode;
Last = baseNode;
baseNode.Parent = baseNode;
NodeList.Add(baseNode);
}
private void FloatLast()
{
BinaryHeapNode <T> temp = Last;
while (temp.Parent.Value != null)
{
if (temp.Value.CompareTo(temp.Parent.Value) < 0)
{
SwapValue(temp, temp.Parent);
temp = temp.Parent;
}
else
{
break;
}
}
}
private void AddNewChild()
{
BinaryHeapNode <T> newNode = new BinaryHeapNode <T>();
newNode.Index = NodeList.Count;
NodeList.Add(newNode);
Last = newNode;
newNode.Parent = NodeList[newNode.Index >> 1];
if (newNode.Parent.Value != null)
{
newNode.Parent.SetChild(newNode);
}
else
{
Root = newNode;
}
}
public void SetChild(BinaryHeapNode <T> childNode)
{
Childs[(childNode.Index & 1)] = childNode;
}