/*

Copyright: 2000, All rights reserved.
Program: DoubleMoney 
Version: 1.0
Created/Revised: 4/2/00
File: doublemoney.cpp
Programmer: C. S. Tritt, Ph.D.
Course: CS-150
Assignment: Example
Compiler: Microsoft Visual C++ 6.0
Target: Win32

Description:

   This program calculates the time to double an investment given some
   specific conditions including a monthly fee. It is based on the example
   on page 237 in Horstmann's CCC 2nd ed.

Revisions:

  There have been no major revisions of this program.

Constants and Variables:

  See code for constant and variable descriptions.

*/

// Included files.

#include <iostream>

// These macros mimic the ANSI C++ logical operations.

#define and &&
#define or ||
#define not !

using namespace std;

int main()
{
   const double MPY = 12.; // Months per year.
   const double PRCNT = 100.; // Percentage conversion.

   // Get user input.

   double apr; // Annual percentage rate.
   cout << "Enter annual percentage rate: ";
   cin >> apr;
   double rate = apr / MPY / PRCNT; // Convert APR to monthly rate.

   double ib; // Initial balance.
   cout << "Enter initial balance: ";
   cin >> ib;
   double fb = 2.0*ib; // Final balance should be twice the initial balance.
   double balance = ib; // The balance starts as the initial balance.

   double fee; // Monthly fee.
   cout << "Enter monthly fee: ";
   cin >> fee;

   int month = 0;

   // Find time to double or loss investment.

   while (balance < fb and balance > 0)
   // alternate condition (not (balance >= fb or balance <=0)) 
   {
      month = month + 1; // Increament month. Alternative month = month + 1
      balance = balance * (1. + rate) - fee;
      cout << balance << "\n";
   }

   // Tell the user what happened.

   if (balance >= fb)
   {
      cout << "You will double your money in " << month << " month(s).\n";
   }
   else
   {
      cout << "Your money will be gone after " << month << " month(s).\n";
   }    

	// Everything worked.

	return 0;
}