/// <summary>
/// Merges two heaps into first one.
/// Both heaps will be modified.
///
/// Time complexity: O(N * lon(M + N)).
///
/// Space complexity: O(N).
///
/// M and N are sizes of both heaps.
/// </summary>
/// <param name="other">Another heap to merge from.</param>
/// <returns>Returns modified heap with elements from both heaps.</returns>
public BinaryHeap <T> Meld(BinaryHeap <T> other)
{
if (other == null)
{
throw new ArgumentNullException(nameof(other));
}
while (!other.IsEmpty)
{
this.Add(other.ExtractMin());
}
return(this);
}
/// <summary>
/// Merges two heaps and returns new one.
/// Initial heaps will not be modified.
///
/// Time complexity: O(M + N).
///
/// Space complexity: O(M + N).
///
/// M and N are sizes of both heaps.
/// </summary>
/// <param name="other">Another heap to merge from.</param>
/// <returns>Returns new binary heap containing elements from both heaps.</returns>
public BinaryHeap <T> Merge(BinaryHeap <T> other)
{
if (other == null)
{
throw new ArgumentNullException(nameof(other));
}
List <T> elements = new List <T>(this.Count + other.Count);
foreach (var item in this.Items)
{
elements.Add(item);
}
foreach (var item in other.Items)
{
elements.Add(item);
}
return(new BinaryHeap <T>(elements, this.Comparer));
}
