Lecture 23 – Design of HeapSort Program

Steps to carry out to build heap

Initialize PositionCounter

While heapArray not full and there is more data

Get number

Increment PositionCounter

Put number in heapArray at PositionCounter

If number being inserted is not at rootPosition — while n != 1

Determine parentPosition

Compare the childValue to its parentValue

If childValue is less than the parentValue

Set childPosition to parentPosition

Elements Needed

Need an array

PositionCounter --last entered element

N -- moving target to get to parent

Subprograms—

Print array

Get number

Swap -- Swap parent and child

Show swap

Get Child

Get Parent

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2^nd part of problem

Sort (i.e. heapsort) Algorithm

LOOP

Swap first and last element in the array

Decrement the last element counter

Find smaller child of 2n and 2n + 1

Swap parent with smaller child

Update parent’s position to smaller child position

Find smaller child

UNTIL the parent’s children’s positions are greater then the last element counter

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Due for Tuesday, November 21^st:

Heap sort program (i.e. specification, body, test) zipped together

Binary Search Tree program –

myHeap2.exe is available at https://users.cs.jmu.edu/adamses/public

it shows you the output from my BUILDHEAP portion of program.

Sample data I used with myHeap2.exe is here heapInput.txt

Here is the package specification I used .HeapUsefulStuff2.ads

If you have trouble opening it, here’s a txt version…