test scores #1

[kohl5555]

book question:
Write a program that dynamically allocates an array large enough to hold a user-defined number of test scores. Once all the scores are entered, the array should be passed to a function that sorts them in ascending order. Another function should be called that calculates
the average score. The program should display the sorted list of scores and averages with appropriate headings. Use pointer notation rather than array notation whenever possible.

Input Validation: Do not accept negative numbers for test scores.

teachers added notes:
Make sure that you use pointers in the program wherever possible.
The program is to ask the user for the number of test scores.

MY PROBLEM:
had similar submission, but i changed code around a bit. my problem is no errors, but it's not showing average. also if you could make sure i used pointers where ever possible that be great.

#include <iostream>
#include <iomanip>

using namespace std;

void arrSelectSort(double *, int);
void showArrPtr(double *, int);
double showAverage(double, int);

int main()
{
	double *scores,                        //To dynamically allocate an array
	total = 0.0,                          //Accumulator
	average;                             //To hold the averge scores
	int numScores;                      //To hold the number of test scores
								       //Get the number of test scores.
	cout << "How many test scores would you like to process?";
	cin >> numScores;

	 //Dynamically allocate an array large enough to hold that many test scores
	scores = new double[numScores];
	if (scores == NULL)
		return 0;

	//Get the test score for each test
	cout << "Enter the test scores below.\n";
	
	for (int count = 0; count < numScores; count++)
	{
		cout << "Test score #" << (count + 1) << ": ";
		cin >> scores[count];
		while (scores[count] <= 0)
		{
			cout << "Zero or negative numbers not accepted.\n";
			cout << "Test Score #" << (count + 1) << ": ";
			cin >> scores[count];
		}
	}

	

	//Calculate the total scores
	for (int count = 0; count < numScores; count++)
	{
		total += scores[count];
	}

	//sort the elements of the array pointers
	arrSelectSort(scores, numScores);

	cout << "The test scores in ascending order are: \n";
	showArrPtr(scores, numScores);
	showAverage(total, numScores);


	return 0;

}

void arrSelectSort(double *array, int size)
{
	int startScan, minIndex;
	double  minElem;
	for (startScan = 0; startScan < (size - 1); startScan++)
	{
		minIndex = startScan;
		minElem = array[startScan];
		for (int index = startScan + 1; index < size; index++)
		{
			if (array[index]  < minElem)
			{
				minElem = array[index];
				minIndex = index;
			}
		}
		array[minIndex] = array[startScan];
		array[startScan] = minElem;
	}
}

void showArrPtr(double *array, int size)
{
	for (int count = 0; count< size; count++)
		cout << array[count] << " ";
	cout << endl;
}
double showAverage(double total, int numScores)
{
	double average;

	//Calculate the average
	average = total / numScores;
	return average;

	//Display the results.
	cout << fixed << showpoint << setprecision(2);
	cout << "Average Score: " << average << endl;
	system("pause");
}

[MikeyBoy]

it's not showing average

That's because lines 96 - 98 will never execute. Can you see why?

[kohl5555]

got it to work, but forgot to post.

#include <iostream>
#include <iomanip>

using namespace std;

void arrSelectSort(double *, int);
void showArrPtr(double *, int);
void showAverage(double, int);

int main()
{
	double *scores,                        //To dynamically allocate an array
		total = 0.0;                        //Accumulator
	//average;                             //To hold the averge scores
	int numScores;                      //To hold the number of test scores
	
    //Get the number of test scores.
	cout << "How many test scores would you like to process?";
	cin >> numScores;

	//Dynamically allocate an array large enough to hold that many test scores
	scores = new double[numScores];
	if (scores == NULL)
		return 0;

	//Get the test score for each test
	cout << "Enter the test scores below.\n";
	
	
	
	for (int count = 0; count < numScores; count++)
	{
		cout << "Test score #" << (count + 1) << ": ";
		cin >> *(scores + count);
		
	}

	

	//Calculate the total scores
	for (int count = 0; count < numScores; count++)
	{
		total += *(scores + count);
	}
	showAverage(total, numScores);
	//sort the elements of the array pointers
	arrSelectSort(scores, numScores);

	cout << "The test scores in ascending order are: \n";
	showArrPtr(scores, numScores);
	

	//Free memory.
	delete[] scores;
	scores = 0;
	
	

	return 0;

	
}

// bubble sort 
void arrSelectSort(double *array, int size)
{
	int temp;
	bool swap;
	do
	{

		swap = false;

		for (int count = 0; count < (size - 1); count++)
		{
			if (*(array + count) > *(array + count + 1))
			{

				temp = *(array + count);
				*(array + count) = *(array + count + 1);
				*(array + count + 1) = temp;
				swap = true;
			}
		}
	} while (swap);
}

// sort function
void showArrPtr(double *array, int size)
{
	for (int count = 0; count< size; count++)
		cout << *(array + count) << " ";
	cout << endl;
}

// average function
void showAverage(double total, int numScores)
{
	double average;

	//Calculate the average
	average = total / numScores;
	

	//Display the results.
	cout << fixed << showpoint << setprecision(2);
	cout << "Average Score: " << average << endl;

}

[kohl5555]

you don't have to change to a bubble sort, but me and the teacher couldn't figure out after a few needed changes why my program wasn't working. changed to a bubble sort and come to realize I had an asterisk inside a one of the array + count codes

like this:

//wrong
(*array + count)

//right
*(array + count)