Source for a Simple C++ Program


/************************************************************************
*

The following is a simple C++ program containing declarations, expressions, statements, and two functions:

                                                                        *
************************************************************************/


/**
 ** A simple C++ program containing declarations,
 ** expressions, statements, and two functions:
 **/

#include <math.h>                         // contains definition of abs()
double multiplier, common_ratio;          // variable declarations
double geo_series(double a, double r)     // function definition
{
      if (r == 1)                         // if statement
            return -1.0;                  // return statement
      else if (abs(r) < 1.0)              // else if statement
            return (a / (1 - r));         // statement containing
                                          // expression
      else return -2.0;
}
void main()                // program execution begins here
{
      double sum;          // variable declaration
      multiplier = 2.2;    // initialization of external variable
      common_ratio = 3.1;  // initialization of external variable
      sum = geo_series(multiplier, common_ratio); // function call
      // ..
}