Chapter 17, Problem 13PE

Program Plan Intro

Computing time results for Heap sort and Merge sort

Program plan:

ArrayUtil.java:

• Include the required header file.
• Define the class “ArrayUtil”.
  • Define a “randomIntArray” method.
    • This function generates random number for sorting
  • Define a “swap()” method.
    • This function swaps the two entries of an array.

MergeSorter.java:

• Define the class “MergerSorter”.
  • Define a “sort()” method.
    • This sorts an array using merge sort.
  • Define a “merge()” method.
    • This function merge the two sorted arrays into an array.

HeapSorter.java:

• Define a class “HeapSorter”.
  • Define a “sort()” method.
    • This function sorts the given array using selection sort.
  • Define a “fixHeap()” method.
    • This function confirms the heap property for a subtree.
    • Ensures that the children nodes fulfil the heap property.
  • Define a “getLeftChildIndex()” method.
    • This returns the left child of the subtree.
  • Define a “getRightChildIndex()” method.
    • This returns the right child of the subtree.

StopWatch.java:

• Define a class “StopWatch”.
  • Define a constructor “StopWatch()”.
    • This generates the stopwatch in stopped state.
  • Define a “start()” function.
    • This starts the stopwatch.
  • Define a “stop()” function.
    • This stops the stopwatch and add this time to elapsed time.
  • Define a “getElapsedTime()”.
    • This returns the total elapsed time.
  • Define a “reset()” function.
    • This resets the elapsed time to 0 and “isRunnning” to false.

SorterTimer.java:

• Define the class “SorterTimer”.
  1. ○ Define the “main()”.
     • Create Scanner object as “in”.
     • Read the input from the user for array size.
     • Generate a random array using “ArrayUtil” class.
     • Create an object for “StopWatch” as “timer”.
     • Call the “Stopwatch” member function “start()”.
     • Next call the “sort()” function from MergeSorter. Then stop the stopwatch using “stop()” function.
     • Print the value of time taken by merge sort.
     • Create an object for “StopWatch” as “timer”.
     • Call the “Stopwatch” member function “start()”.
     • Next call the “sort()” function from “HeapSorter”. Then stop the stopwatch using “stop()” function.
     • Print the value of time taken by heap sort.