So I currently taking a class in C++ which I find difficult only because I am not so experienced. I was wondering if anyone can help me figure out a while loop to calculate a single monthly payment for this program.

//Amortization Formula: R = L * i -------------------- 1 - (1 + i)^-mt #include <iostream> #include <cmath> #include <iomanip> using namespace std; double R; // amortization formula double L = 0.00; // loan amount (principal) double g; // gross salary double r; // interest rate per year int t = 30; // number of years for the loan int m = 12; // number of payments in a year double i = m / t; int p; // monthly payment range int grossSalary(); // prototype function of grossSalary double interestRate(); // prototype function of interestRate double monthlyPaymentRange(); // prototype function of monthlyPaymentRange double maxTarget(); // prototype function of maxTarget double monthlyPayment(); // prototype function of monthlyPayment int main() // this combines all of the functions in order to give the monthly payment { grossSalary(); interestRate(); monthlyPaymentRange(); maxTarget(); monthlyPayment(); system("pause"); } int grossSalary() // this function asks for the gross salary of the user and returns g (gross salary) { cout << "Please enter your yearly gross salary: "; cin >> g; return g; } double interestRate() // this function asks the user for an interest rate and returns r (interest rate) { cout << "Please enter an interest rate: "; cin >> r; return r; } double monthlyPaymentRange() // this function calculates the monthly payment range { p = g / 12 * 0.3; cout << "The target (30% of monthly salary) monthly payment range is: " << p << endl; return p; } double maxTarget() // this function calculates the maximum target house price { L = g * r - g; cout << "Your max target house price is: " << L << endl; return L; } double monthlyPayment() // this function calculates the monthly payment using the amortization formula { cout << "with a monthly payment of: " << R << endl; while(L < p) // how to fix this? { cout << R << endl; R = L * i / 1 - pow(1 + i, -m * t); break; } return R; }

I am completely stuck and don't know how to go about it. Any help would be great.

**Edited by YNV_DeViouS, 02 August 2014 - 11:06 AM.**