Error when testing user input

[DirtyPowder]

I am creating a program for my class that gets ten integers from the user, stores them in an array. Then passes that information to a function to compute the average for those ten numbers. I have the program finished (although any tips are welcome) and am now testing. When I fill the array with all zeros the sum of everything comes to 3.76505e-039. Is this common? And is there a way to change it so the sum equals 0?

Here is my code.

#include <cstdlib>
#include <iostream>

/****************************************************/
/* File: name of your file with the source code     */
/*                                                  */
/* Created by: Aaron Criswell                       */
/* Date: 15 Aug 2011                                */
/*                                                  */
/* Program to compute average from array            */
/*                                                  */
/* Inputs: (keyboard)                               */
/*   Ten integers numbers[10]                       */
/*                                                  */
/* Output:                                          */
/*   Average of ten user supplied integers          */
/*                                                  */
/*                                                  */
/****************************************************/

using namespace std;

//prototype function
void average(float avg[], int sizeOfArray);

int main()
{
    char cont = 'y';
    
    do
    {
    //declare and initialize variables
    int i = 0;
    float numbers[10] = {0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0};
    
    //print instructions and request for user input
    cout <<"This program will calculate the average for ten positive integers." << endl; 
    cout <<"Please enter your numbers now." << endl;
    cout << endl;
    
    //cycles through array for user input
    for (i=0; i<10; i++)
    {
        cout <<"Enter integer #" << i+1 << ": ";
        cin >> numbers[i];
        cin.ignore();
        cout << endl;
    }
    
    //test to see array data
    //    for (i=0; i<10; i++)
    //{
    //    cout << numbers[i] << endl;
    //}
    
    //call average function
    average(numbers, 10);
    cout << endl;
    
    cout <<"Would you like to try again? (Y/N):  ";
    cin >> cont;
    cin.ignore();  
    }
    //gives user option to continue
    while (cont == 'Y' || cont == 'y');
    
    return EXIT_SUCCESS;
}


void average(float avg[], int sizeOfArray)
{ 
      //declare and initialize variables
      int i = 0;
      float x = 0.0;
      float sum = 0.0;
      float n = 0.0;
      
      //loop to add array input, then divide to get average
      for (i=0; i<=sizeOfArray; i++)
          {
                x = avg[i];
                sum = sum + x;
                n = sum / sizeOfArray;
          }
      cout << endl;    
            
      cout << "The average for your number set is:  " << n << endl;    
}

[shacktar]

In your loop, i<=sizeOfArray should be i<sizeOfArray because sizeOfArray-1 is the last index.

[DirtyPowder]

Thank you. It works now and makes since to me. The function was grabbing garbage because I had the for loop set to cycle 1 to many times. I will have to work on paying attention to detail more.

[kempofighter]

Also, you are calculating the average over and over in the loop. That isn't necessary. You should wait until you have summed everything and then calculate the average.

Since you are a student, I can understand why you would write your own loops, but for future reference, it is better to use std algorithms to perform common tasks. Take a look at these links.
http://cplusplus.com/reference/std/numeric/accumulate/
http://cplusplus.com/articles/zvbCpfjN/