// average6.cpp
// Averages a sequence of integers entered by the user.
// The number of numbers to be averaged is decided
// in advance by the user and is error-checked
// to ensure that it is a positive integer.
// Demonstrates count-controlled repetition.
// Uses a for loop.

#include <iostream>
using namespace std;

int main()
{
   // Announce purpose of program:
   cout << "This program averages a sequence of integers "
             << "entered by the user." << endl << endl;

   // Ask user for length of sequence of numbers to be averaged:
   cout << "Enter the number of numbers to be averaged:>";
   int numberOfNumbers;
   cin >> numberOfNumbers;

   // Error-check length of sequence:
   if ( numberOfNumbers <= 0 )
   {
      cout << "The number of numbers, " << numberOfNumbers
             << ", is invalid.  Must be > 0." << endl;
      return 1;
   }  // if

   // Calculate cumulative sum of numbers entered:

   int sum = 0;        // cumulative sum
   cout << "Enter the numbers:> ";

   for ( int i = 0;  i < numberOfNumbers;  i++ )
   {
      // Read current input number:
      int number;
      cin >> number;

      // Add number to cumulative sum:
      sum += number;
   }  // for i

   // Compute the average and output the result:
   float average = (float) sum / numberOfNumbers;
   cout << "The average is: " << average << "." << endl;

   return 0;
}  // function main