SOURCE FILE: floorSpace03.cpp

/* 
   Program to display the floor space for a room   
   
   Fleshed-out design. 
     * Now there are declarations of the variables 
       used in the main function
     * Now there are prototypes for the functions
        + prototypes tell 
           - what data type, if any the function returns
           - the name of the function
           - the number and types of parameters required by the function
     * Now there are also definitions of the functions
         + the function definitions have only STUB CODE,
           not FINISHED CODE.
         + STUB CODE is place-holder code that allows
           us to compile and run the program for the purpose
           of checking that the main function is correct
      * As indicated above, this program can be compiled and executed.
        The result of doing that is to get output that shows that the 
        program is calling the functions and performing its other 
        actions in the right order, and using the right logic and
        flow of control.
        
*/

#include <iostream>
using namespace std ;

/* ================================== */
/* FUNCTION DECLARATIONS (PROTOTYPES) */
/* ================================== */

void directions(void);
       /* Print directions for using the program. */

int  GetDim(void);   
       /* Prompt the user for one dimension of a floor and 
          return that dimension */

int area(int length, int width);   
       /* Return the floor space (area of the floor) 
          given two dimensions (length and width). */

/* ================================== */
/* ================================== */

int main(void)   
{   
   int dim1,               // one dimension of the room     
       dim2,               // another dimension of the room 
       FloorSpace;         // area of floor in room         

         /* Step One: Print Directions for the user */
  directions() ;

        /* Step Two: Get the dimensions of the floor from the user */
  dim1 = GetDim();   
  dim2 = GetDim(); 
   
       /* Step Three: IF   either dimension is not positive
                           print an error message
                      ELSE Compute FloorSpace as product and 
                           print the answer out for the user to see
       */
  if ( (dim1 <= 0) || (dim2 <= 0) )      // invalid data 
   {    
      cout << "\nSorry, only positive dimensions are allowed.\n";
      cout << "Please reexecute the program.\n\n";
   }   
  else  // valid data 
   {   
      FloorSpace = area(dim1, dim2);   
      cout << "\nThe floor space is " << FloorSpace << " square feet.\n\n";
   }   

   return 0;
}   

/* ================================== */
/*       FUNCTION DEFINITIONS         */
/* ================================== */

/* ================================== */
/*           ALL ARE STUBS            */
/* ================================== */

/* ================================== */
void directions(void)   
{   
      // stub output so we will know when the function runs
   cout << "Entering function 'directions' \n" ;
}   
/* ================================== */
      

/* ================================== */
int GetDim(void)   
{   
      // stub output so we will know when the function runs
   cout << "Entering function 'GetDim' \n" ;

      /* return SOMETHING, so that the caller gets a value 
         back from the function. */
   return 39 ; // arbitrary return value
}   
/* ================================== */
   
   
/* ================================== */
int area(int dim1, int dim2)   
{   
      // stub output so we will know when the function runs
   cout << "Entering function 'area' \n" ;

      /* stub output tells what the values of the 
         parameters are, so we know that the function
         received the correct thing from the caller */
   cout << "dim1 is: " << dim1 << endl ;
   cout << "dim2 is: " << dim2 << endl ;

      /* return SOMETHING, so that the caller gets a value 
         back from the function. */
   return 42 ;// arbitrary return value
}   
/* ================================== */