/// <summary>
/// Removes an element with maximum priority.
/// </summary>
/// <returns>The element removed.</returns>
public TValue RemoveMaximumPriority()
{
if (_elements == null)
{
throw new InvalidOperationException();
}
else
{
TValue tempValue = _elements.Data.Value;
_count--;
_elements = Merge(_elements.LeftChild, _elements.RightChild);
return(tempValue);
}
}
/// <summary>
/// Constructs a LeftistTree with the given data, and children.
/// </summary>
/// <param name="data">The data stored in the node.</param>
/// <param name="child1">One child.</param>
/// <param name="child2">The other child.</param>
public LeftistTree(T data, LeftistTree <T> child1, LeftistTree <T> child2)
{
_data = data;
if (NullPathLength(child1) < NullPathLength(child2))
{
_rightChild = child1;
_leftChild = child2;
}
else
{
_rightChild = child2;
_leftChild = child1;
}
_nullPathLength = NullPathLength(_rightChild) + 1;
}
/// <summary>
/// Merges the given heaps into one.
/// </summary>
/// <param name="h1">One heap.</param>
/// <param name="h2">The other heap.</param>
/// <returns></returns>
private static LeftistTree <KeyValuePair <TPriority, TValue> > Merge(LeftistTree <KeyValuePair <TPriority, TValue> > h1,
LeftistTree <KeyValuePair <TPriority, TValue> > h2)
{
if (h1 == null)
{
return(h2);
}
else if (h2 == null)
{
return(h1);
}
else
{
int compare = h1.Data.Key.CompareTo(h2.Data.Key);
if (compare > 0)
{
return(new LeftistTree <KeyValuePair <TPriority, TValue> >(h1.Data, h1.LeftChild, Merge(h1.RightChild, h2)));
}
else
{
return(new LeftistTree <KeyValuePair <TPriority, TValue> >(h2.Data, h2.LeftChild, Merge(h2.RightChild, h1)));
}
}
}