// IEA 1996
// Example program - section 23.4
// A test program for the functions meanarray
// and addarray.

#include <iostream.h>
#include <iomanip.h>

// Function prototypes

float meanarray(int,float[]);
void addarray(int,const float[],const float[],float[]);
void printarray(int,const float[]);

void main()
{
 const int MAX = 10;
 float arr1[MAX] = {1.0,2.1,3.4,4.1,5.2,2.4,5.1,6.3,2.5,1.9},
       arr2[MAX] = {3.1,2.3,6.2,8.1,2.5,5.1,2.8,1.6,4.2,5.1},
       arr3[MAX];
 float average;
 int i;
 average = meanarray(MAX,arr1);
 cout << "The array with elements " 
      << endl;
 printarray(MAX,arr1);
 cout << endl << "has average value of "
      << average << endl;
 addarray(MAX,arr1,arr2,arr3);
 cout << endl << "The sum of the arrays "
      << endl;
 printarray(MAX,arr1);
 cout << endl << "and" << endl;
 printarray(MAX,arr2);
 cout << endl << "is" << endl;
 printarray(MAX,arr3);
}

// Function definitions

float meanarray(int n,        // IN no of elements
                float A[])    // IN array parameter
     // This function returns the average value of
     // the first n elements in the array A which
     // is assumed to have >= n elements.
  {
    float sum = 0.0;     // local variable to
                         // accumulate sum
    int i;               // local loop control
    for (i = 0; i < n; i++)
        sum += A[i];

    return sum/n;
  }  // end meanarray

void addarray(int size,         // IN size of arrays
              const float A[],  // IN input array
              const float B[],  // IN input array
              float C[])        // OUT result array

     // Takes two arrays of the same size as input
     // parameters and outputs an array whose elements
     // are the sum of the corresponding elements in
     // the two input arrays.

  {
    int i;     // local control variable
    for (i = 0; i < size; i++)
         C[i] = A[i] + B[i];

  } // End of addarray

void printarray(int n,const float A[])
   
   // Prints the first n elements of the array A
   // five to a row.

   {
    int i;
    cout << setiosflags(ios::fixed | ios::showpoint)
         << setprecision(1);
    for (i=0; i<n; i++)
       {
        if (i%5 == 0)
           cout << endl;
        cout << setw(6) << A[i];
       }
    cout << endl;
   }