/// <summary>
/// Merges two priority queues and sets specified comparer for resultant priority queue
/// </summary>
/// <param name="pq1">first priority queue</param>
/// <param name="pq2">second priority queue</param>
/// <param name="comparer">comparer for resultant priority queue</param>
/// <returns>resultant priority queue</returns>
public static PriorityQueue <TPriority, TValue> MergeQueues(PriorityQueue <TPriority, TValue> pq1, PriorityQueue <TPriority, TValue> pq2, IComparer <TPriority> comparer)
{
if (pq1 == null || pq2 == null || comparer == null)
{
throw new ArgumentNullException();
}
// merge data
PriorityQueue <TPriority, TValue> result = new PriorityQueue <TPriority, TValue>(pq1.Count + pq2.Count, pq1._comparer);
result._baseHeap.AddRange(pq1._baseHeap);
result._baseHeap.AddRange(pq2._baseHeap);
// heapify data
for (int pos = result._baseHeap.Count / 2 - 1; pos >= 0; pos--)
{
result.HeapifyFromBeginningToEnd(pos);
}
return(result);
}
/// <summary>
/// Merges two priority queues
/// </summary>
/// <param name="pq1">first priority queue</param>
/// <param name="pq2">second priority queue</param>
/// <returns>resultant priority queue</returns>
/// <remarks>
/// source priority queues must have equal comparers,
/// otherwise <see cref="InvalidOperationException"/> will be thrown
/// </remarks>
public static PriorityQueue <TPriority, TValue> MergeQueues(PriorityQueue <TPriority, TValue> pq1, PriorityQueue <TPriority, TValue> pq2)
{
if (pq1 == null || pq2 == null)
{
throw new ArgumentNullException();
}
if (pq1._comparer != pq2._comparer)
{
throw new InvalidOperationException("Priority queues to be merged must have equal comparers");
}
return(MergeQueues(pq1, pq2, pq1._comparer));
}