mergePQ -- merges two queues

Synopsis

Usage:

Q = mergePQ(Q,R)
Inputs:
- Q, an instance of the type PriorityQueue,
- R, an instance of the type PriorityQueue,
Outputs:
- Q, an instance of the type PriorityQueue, the same PriorityQueue as the first input, now with the second merged into it

Description

The output of the function is the priority queue whose elements are the disjoint union of the elements of Q and R. Note that Q is altered in the process to become the merged queue.

i1 : Q = priorityQueue {2,4,6}

o1 = PriorityQueue{...4...}

o1 : PriorityQueue

i2 : R = priorityQueue {1,3,5}

o2 = PriorityQueue{...4...}

o2 : PriorityQueue

i3 : mergePQ(Q,R)

o3 = PriorityQueue{...4...}

o3 : PriorityQueue

i4 : pop Q

o4 = 1

i5 : pop Q

o5 = 2

Caveat

The priority queue Q is mutable and is altered by mergePQ. The elements of Q and R must be comparable to each other.

Ways to use mergePQ :

mergePQ(PriorityQueue,PriorityQueue)

For the programmer

The object mergePQ is a method function.