Counting # of comparisons in a quick sort and printing them

For part of a homework, my program has to output the number of comparisons of data elements made by a quick sort and an insertion sort.  I got the insertion sort to work. Not so the quick sort.

I have added a counter to the quickSort method provided, but it is in a loop and just keeps printing forever. I have tried putting the counter elsewhere and get an "unreachable" error.  
Would you please look at my code and tell me where I have messed up?
I can provide the program where I call the quickSort function if that helps.

Many, many thanks for helping me get this straight!!
 Jo


//Quick sort algorithm.
  //Postcondition: list objects are in ascending order.
  public void quickSort(T[] list, int length)
  {
    recQuickSort(list, 0, length - 1);
  }//end quickSort
  
  //Method to partition the list between first and last.
  //The pivot is choosen as the middle element of the list.
  //This method is used by the recQuickSort method.
  //Postcondition: After rearranging the elements,
  //               according to the pivot, list elements
  //               between first and pivot location - 1,
  //               are smaller the the pivot and list
  //               elements between pivot location + 1 and
  //               last are greater than or equal to pivot.
  //               The position of the pivot is also
  //               returned.
  private int partition(T[] list, int first, int last)
  {
    T pivot;
    
    int smallIndex;
    int counter = 0;         //initialize counter
    swap(list, first, (first + last) / 2);
    
    pivot = list[first];
    smallIndex = first;
    
    for (int index = first + 1; index <= last; index++)
    { 
      Comparable<T> compElem = (Comparable<T>) list[index];
      counter=counter+1;        //increment counter
      
      if (compElem.compareTo(pivot) < 0)
      {
        smallIndex++;
        swap(list, smallIndex, index);
        
      }

    }

        System.out.print(counter);   // print out number of comparisons
     System.out.print("The total number of comparisons in the quickSort was  ");
    swap(list, first, smallIndex);
    
    return smallIndex;
        

} 
  //end partition

//Method to sort the elements of list between first
//and last using quick sort algorithm,
//Postcondition: list elements between first and last
//               are in ascending order.
private void recQuickSort(T[] list, int first, int last)
{
 
  if (first < last)
  {
    int pivotLocation = partition(list, first, last);
    recQuickSort(list, first, pivotLocation - 1);
    recQuickSort(list, pivotLocation + 1, last);
    
  }

}//end recQuickSort

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jovanvlietAsked:
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CEHJCommented:
Make 'counter' an instance variable and do
    //Quick sort algorithm.
    //Postcondition: list objects are in ascending order.
    public void quickSort(T[] list, int length) {
	recQuickSort(list, 0, length - 1);
	System.out.printf("The total number of comparisons in the quickSort was %d\n", counter);
    } //end quickSort

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jovanvlietAuthor Commented:
Thanks!
It looks like it would work, but when I paste it in and run the programs, it says it can't find counter (which it can't because counter get initialized later).
Have I just messed up copying your code into my program? I'll attach the folder with the SearchSortAlgorithms, SearchSortADT and my test file
ExamInsertionQuickSort4-files--2.zip
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CEHJCommented:
>>it says it can't find counter (which it can't because counter get initialized later).

It must be an instance variable of the class containing the sorting methods
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Mick BarryJava DeveloperCommented:
see comments below:

//Quick sort algorithm.

   // make counter a member variable

   private int counter = 0;         //initialize counter

  //Postcondition: list objects are in ascending order.
  public void quickSort(T[] list, int length)
  {
    recQuickSort(list, 0, length - 1);
    // print out counter once all done
        System.out.print(counter);   // print out number of comparisons
     System.out.print("The total number of comparisons in the quickSort was  ");

  }//end quickSort
 
  //Method to partition the list between first and last.
  //The pivot is choosen as the middle element of the list.
  //This method is used by the recQuickSort method.
  //Postcondition: After rearranging the elements,
  //               according to the pivot, list elements
  //               between first and pivot location - 1,
  //               are smaller the the pivot and list
  //               elements between pivot location + 1 and
  //               last are greater than or equal to pivot.
  //               The position of the pivot is also
  //               returned.
  private int partition(T[] list, int first, int last)
  {
    T pivot;
   
    int smallIndex;
    swap(list, first, (first + last) / 2);
   
    pivot = list[first];
    smallIndex = first;
   
    for (int index = first + 1; index <= last; index++)
    {
      Comparable compElem = (Comparable) list[index];
      counter=counter+1;        //increment counter
     
      if (compElem.compareTo(pivot) < 0)
      {
        smallIndex++;
        swap(list, smallIndex, index);
       
      }

    }

    swap(list, first, smallIndex);
   
    return smallIndex;
       

}
  //end partition

//Method to sort the elements of list between first
//and last using quick sort algorithm,
//Postcondition: list elements between first and last
//               are in ascending order.
private void recQuickSort(T[] list, int first, int last)
{
 
  if (first < last)
  {
    int pivotLocation = partition(list, first, last);
    recQuickSort(list, first, pivotLocation - 1);
    recQuickSort(list, pivotLocation + 1, last);
   
  }

}//end recQuickSort
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jovanvlietAuthor Commented:
Thank you!  Great solution! It works perfectly and I have learned something new.

Many, many thanks!!!
Jo
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jovanvlietAuthor Commented:
Great solution that worked perfectly and taught me a new bit about Java as well.
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jovanvlietAuthor Commented:
Hi,
I'm new at this.
I meant to assign 400 point to object for an outstanding solution and 100 point to CEHJ for making a great suggestion based onmy llimited input.

If I didn't get them assigned like that,would you let me know or fix it?

I REALLY appreciate the help!
0
CEHJCommented:
>>I meant to assign 400 point to object for an outstanding solution and 100 point to CEHJ

I find that odd. The only difference between what i posted and objects posted is that he's repeated more of your code, and showed the instance variable, which i didn't think necessary.

>>If I didn't get them assigned like that,would you let me know or fix it?

I'll get the question reopened
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