I have put together a program using a class AbstractSort that can be used to analyze the number of comparisons performed by a sorting algorithm. Anyway, I built the programs( I have 2 here) and the first one counts the passes but does not order the array created and the second one does better with the array but I lose the counting function somehow. Any ideas where I screwed up?
PROGRAM 1

// This Program uses a class named AbstractSort as a framework
// For sorting algorithms that sort by comparing pairs of array entries.
// To obtain a concrete class for sorting, one first subclasses
// The AbstractSort class and then overrides the pure virtual function
// Sort. The sort() function must call the compare(int, int) function
// To compare pairs of array entries.
*/

#include <iostream>
#include <iomanip>
#include <string>
#include <cmath>
#include <algorithm>	
#include <cstdlib> 		
using namespace std;



class AbstractSort					
{
public:
	virtual void sort(int arr[], int size) = 0;
	int getComparisonCount()
	{
		return comparisonCount;
	}
		void resetComparisonCount()
	{
			comparisonCount= 0;
	}

protected:
			int compare(int x, int y);
private:
			int comparisonCount;
};

//	AbstractSort::compare
//		Returns  -1, 0, or 1 a la strcmp
//		This also keeps track of the number of comparisons performed

int	AbstractSort:: compare(int x, int y)	//compare func
		{
			comparisonCount++;
			return x -x;
		}
// derived class
		class MaxSort : public AbstractSort
		{
		public:
			void sort(int arr[], int size);
		};
		//MaxSort::sort  sort the given array with the given number of elements
		void MaxSort::sort (int arr[], int size)
		{
			resetComparisonCount();
			for (int k = size = size-1; k>=1; k--)
			{
			int indexOfLargest =0;
			for (int ix = 1; ix <= k; ix++)
			{
				if (compare (arr[ix], arr[indexOfLargest]) > 0)
				{
					indexOfLargest = ix;
				}
			}
		swap(arr[indexOfLargest], arr[k]);
			}
		}
	
int main()
{
    const int MAX_SIZE = 100;
    int arr[MAX_SIZE];
    int size;
    
    // Explain the program
    cout << "This program keeps track of the number of comparisons required to\n"; 
    cout << "to sort a randomly generated array.\n";
    cout << "How large do you want the array to be? ";
    
    // Get the size of the array
    cin >> size;    
    if (size > MAX_SIZE) 
    {
        cout << "The size of the array must be no greater than 100.";
        exit(1);
    }
    
    // Initialize random number generator
    srand(time(0));
    
    // Fill the array with random numbers
    for (int k = 0; k < size; k++)
      { 
		  arr[k] = rand() % 1000;
	  }
    // Output array to be sorted
    cout << "Array to be sorted is: \n";
    for (int k = 0; k < size; k++)
	{
        cout << arr[k] << "  ";
	}
    // Sort and output results
    MaxSort maxSort;
    maxSort.sort(arr, size);
    cout << "\nThe sorted array is: \n";
    for (int k = 0; k < size; k++)
	{
        cout << arr[k] << "  ";
	}
    cout << "\nNumber of comparisons performed is: " << maxSort.getComparisonCount() << endl;
	
 
	system("pause");
	return 0;
}

PROGRAM 2

#include <iostream>
#include <iomanip>
#include <string>
#include <cmath>
#include <algorithm>	
#include <cstdlib> 		
using namespace std;


class AbstractSort					
{
public:
	virtual void sort(int arr[], int size) = 0;
	int getComparisonCount()
	{
		return comparisonCount;
	}
		void resetComparisonCount()
	{
			comparisonCount= 0;
	}

protected:
			int compare(int x, int y);
private:
			int comparisonCount;
};

//	AbstractSort::compare
//		Returns  -1, 0, or 1 a la strcmp
//		This also keeps track of the number of comparisons performed

int	AbstractSort:: compare(int x, int y)	//compare func
		{
			comparisonCount++;
			return x - y;
		}
// derived class
		class MaxSort : public AbstractSort
		{
		public:
			void sort(int arr[], int size);
		};
		//MaxSort::sort  sort the given array with the given number of elements

		void MaxSort::sort (int arr[], int size)
		{
			resetComparisonCount();
			    int indexOfMin; 
				int pass; 
				int j; 

			for ( pass = 0; pass < size - 1; pass++ ) 
			{ 
				indexOfMin = pass; 

				 for ( j = pass + 1; j < size; j++ ) 
					if ( arr[j] < arr[pass] ) 
						indexOfMin = j; 

					swap ( arr[pass], arr[indexOfMin] ); 
			} 
		} 

// swap function for integers 
void swap ( int& x, int& y ) 
{ 
   int temp; 
   temp = x; 
   x = y; 
   y = temp; 
} 
	
int main()
{
    const int MAX_SIZE = 100;
    int arr[MAX_SIZE];
    int size;
    
    // Explain the program
    cout << "This program keeps track of the number of comparisons required to\n"; 
    cout << "to sort a randomly generated array.\n";
    cout << "How large do you want the array to be (max size=100)? ";
    
    // Get the size of the array
    cin >> size;    
    if (size > MAX_SIZE) 
    {
        cout << "The size of the array must be no greater than 100.";
        exit(1);
    }
    
    // Initialize random number generator
    srand(time(0));
    
    // Fill the array with random numbers
    for (int k = 0; k < size; k++)
      { 
		  arr[k] = rand() % 1000;
	  }
    // Output array to be sorted
    cout << "Array to be sorted is: \n";
    for (int k = 0; k < size; k++)
	{
        cout << arr[k] << "  ";
	}
    // Sort and output results
    MaxSort maxSort1;
    maxSort1.sort(arr, size);
    cout << "\nThe sorted array is: \n";
    for (int k = 0; k < size; k++)
	{
        cout << arr[k] << "  ";
	}
    cout << "\nNumber of comparisons performed is: " << maxSort1.getComparisonCount() << endl;
	
 
	system("pause");
	return 0;
}

Program 1 has a bad compare function. See if you can spot the problem.

int	AbstractSort:: compare(int x, int y)	//compare func
		{
			comparisonCount++;
			return x -x;
		}

Program 2 doesn't appear to USE its compare function, so whether it's right or wrong is irrelevant.

Yeah, I seeit. x-x. Funny how that made it into there and not the second version- they were copied across. Thanks on the first issue, but where am i missing the call on the second. I am taking this c++ class and html AND java along withthe javascript in the html. so I am having languages running together

>> where am i missing the call on the second.

Do a search for the word "compare" in Program 2 and notice that it's never called. Do the same search in Program 1 and note where it's used. Since you say Program 2 sorts properly and since to do so requires comparisons, presumably you're comparing somewhere without calling "compare", so presumably you must have lines within your sort function with comparison operators < > <= >= ==. Find them and change them so they call the "compare" function.

Thanks, that makes sense. I understand why we are spending so much time on polymorphism and virual calls now.

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