//  A sample program that computes volumes of four-sided pyramids
//    with square bases.

#include <iostream>
using namespace std;
#include <stdio.h>

void Hello( void );
void DisplayMenu( void );
void ComputeOnce( void );
void ComputeDifference( void );
void MakeTable( void );
void Goodbye( void );

void main( void )
{
    int choice;

    Hello();

    do
    {
        DisplayMenu();
        cout << "Enter your selection: ";
        cin >> choice;

        if ( choice == 1 ) 
            ComputeOnce();
        else if ( choice == 2 )
            ComputeDifference();
        else if ( choice == 3 )
            MakeTable();
        else if ( choice != 4 )
        {
            cout << endl << "Please enter a number from 1 to 4"; 
            cout << endl << endl;
        }
    }
    while ( choice != 4 );

    Goodbye();
}

void Hello( void )
{
	cout << endl;
	cout << "          Pyramid Volume Calculations" << endl;
	cout << endl;
	cout << "   Compute the volume of square-based pyramids" << endl;
	cout << endl << endl;
}

void Goodbye( void )
{
	cout << endl;
	cout << "Have a nice day." << endl;
	cout << endl << endl;
}

void DisplayMenu( void )
{
	cout << endl;
	cout << "Choose from the following options..." << endl;
	cout << "(1) Compute the volume of one pyramid" << endl;
	cout << "(2) Compute the difference between" << endl;
	cout << "     the volume of two pyramids" << endl;
	cout << "(3) Make a table of pyramid volumes" << endl;
	cout << "(4) Exit the program" << endl;
}

void ComputeOnce( void )
{
  cout << "ComputeOnce" << endl;
}

void ComputeDifference( void )
{
  cout << "ComputeDifference" << endl;
}

void MakeTable( void )
{
  cout << "MakeTable" << endl;
}