getAverage() dropping last element - c++

Question

My average function is dropping the last element.
I tested it using the numbers 0, 5, 10, 20 in which I get an average of 5.00 instead of 8.75.
If you switch the numbers around, the last element still gets dropped.
Also, there's another problem that happened when my teacher tried to run it, but one I've been unable to replicate which is some weird large number getting thrown in the first element after being sorted.
#include <iostream>
#include <cstdlib>
#include <string>
#include <iomanip>
using namespace std;
int getNumber();
void getMovieData(int *, int);
void sort(int *, int);
double getAverage(int *, int);
void print(int *, int);
int main()
{
int students, i, j;
int *movies;
cout << "Enter the number of Students surveyed: ";
i = getNumber();
movies = new int[i];
getMovieData(movies, i);
cout << endl << "--- Here is the data you entered ---" << endl;
print(movies, i);
cout << endl << "--- Here is the data after being sorted --" << endl;
sort(movies, i);
double average = getAverage(movies, i);
print(movies, i);
cout << endl << "The average number of movies seen is " << fixed
<< showpoint << setprecision(2) << average << endl; //rounding to
system("PAUSE");
return 0;
}
// Function used to input positive number
int getNumber()
{
int number;
cin >> number;
// Validation
while (number < 0)
{
cout << endl << "Number cannot be negative: "
"Please enter a nonnegative value: ";
cin >> number;
}
return (number);
}
// Function to input values into the array, movies of size SIZE
void getMovieData(int *ptrToArray, int SIZE)
{
for (int i = 0; i < SIZE; i++)
{
cout << endl << "Enter the number of movies Student " << i+1 << " saw: ";
ptrToArray[i]= getNumber();
}
}
// Bubble Sort the Data
void sort( int *ptrToArray, int SIZE)
{
for (int j = 0; j < SIZE; j++)
{
for (int i = 0; i < SIZE; i++)
{
if (ptrToArray[i] < ptrToArray[i+1])
{
int temp = ptrToArray[i];
ptrToArray[i] = ptrToArray[i+1];
ptrToArray[i+1] = temp;
}
}
}
}
// Simple Average function; returns average to average in main
double getAverage(int *ptrToArray, int SIZE)
{
double total=0;
for(int i=0; i < (SIZE); i++)
{
total += ptrToArray[i];
}
double average = total/(SIZE -1);
return (average);
}
//A function to print the arrays only! the average is printed in main
void print(int *ptrToArray, int SIZE)
{
for (int i = 0; i < SIZE; i++)
{
cout << ptrToArray[i] << setw(10);
}
}
The numbers to input are this:
4
0
5
10
20
with an output of 20, 10, 5, 0 and average of 5.00
and the second set of numbers is:
4
4
22
3
55
with an output of 225982769 55 22 4 (sorted) and average of 32283264.29
With the second set of numbers, I was unable to replicate the output she got as I got the correct sort, but obviously the wrong average. Any help you can give me is much appreciated.
EDIT: There was an issue with the compiler not including the file I was working with in the Project and instead, using the old one. The only difference was
total/7
versus
total/SIZE
which is why the average was off. It SEEMED like it was dropping the last element but it really just so happened to be a coincidence that they totaled 35 and divided by 7 is 5.00 which is also the average if you dropped the 20.
Once I changed the right .cpp file, it worked perfectly (pretty much all the changes you guys suggested had been the original code, and were changes I made to try and alter the average, which didn't change because I wasn't altering the right source file. In short, problem solved.)

Answer 1

You need to include the last element in you averaging function. Either do
for(int i = 0; i < SIZE; ++i)
or
for(int i = 0; i <= (SIZE - 1); ++i)

Answer 2

You have an off-by-one error
for(int i=0; i < (SIZE - 1); i++)
You need i < SIZE. Same goes for the division,
double average = total/(SIZE -1);
Here you need SIZE, not SIZE-1 too.
Also,
system("PAUSE");
Should be avoided. It's better to use something like getchar().