//	File name:	homework4.cpp
//	Author:		Miles Long
//	Instructor:	Dr. John Wang
//	Due date:	Wed., Sept. 26, 2007
//	Compilation:	g++ homework4.cpp -o homework4.out
//	Execution: 	./homework4.out
//
//	Goal:	This program will display the balance of 3 payments
//

#include <iostream>
#include <iomanip>	// setprecision

using namespace std;

int main()
{
	//declare variables
	float bal, pmt, i, ar;
	int k, n;

	cout << fixed << showpoint << setprecision(2);

	//Input
	cout << "\n\nInput your monthly payment (-1 to quit): ";
	cin >> pmt;

	while ( pmt > -1)	
	{
		cout << "Input your Annual Interest Rate in decimal form(0.0#): ";
		cin >> i;
		ar = i/12.0;
		
		cout << "Input your number of payments: ";
		cin >> n;	

		// output ..
		cout << "\n\nMonthly payment:\t$" << pmt << "\n";
		cout << "Annual Interest Rate:\t" << ar*12*100 << "%\n";	
		cout << "# of total payments is:\t" << n << "\n\n";
		
		// computing for payment(s)
		k = 1;
		bal = pmt * ((1 - pow(1 + ar, k - n)) / ar );
		cout << "\nBalance after " << k << " payment(s) is: $" << bal << "\n";

		k = 2;
		bal = pmt * ((1 - pow(1 + ar, k - n)) / ar );
        	cout << "Balance after " << k << " payment(s) is: $" << bal << "\n";
		
		k = 3;
		bal = pmt * ((1 - pow(1 + ar, k - n)) / ar );
		cout << "Balanace after " << k << " payments(s) is: $" << bal << "\n";	
	
		k = 4;
		bal = pmt * ((1 - pow(1 + ar, k - n)) / ar );
                cout << "Balanace after " << k << " payments(s) is: $" << bal << "\n";
		
		cout << "\n\nInput your monthly payment (-1 to quit): ";
       		cin >> pmt;

	}
	
	return 0;

}