listing02.11.ComputeLoan.cpp

#include <iostream>
#include <cmath>
using namespace std;

int main()
{
    // Enter yearly interest rate
    cout << "Enter yearly interest rate, for example 8.25 : ";
    double annualInterestRate;
    cin >> annualInterestRate;

    // Obtain monthly interest rate
    double monthlyInterestRate = annualInterestRate / 1200;

    // Enter number of years
    cout << "Enter number of years as an integer, for example 5: ";
    int numberOfYears;
    cin >> numberOfYears;


    // Enter loan amount
    cout << "Enter loan amount, for example 120000.95: ";
    double loanAmount;
    cin >> loanAmount;

    // Calculate payment
    double monthlyPayment = loanAmount * monthlyInterestRate /
        (1 - 1 / pow(1 + monthlyInterestRate, numberOfYears * 12));
    double totalPayment = monthlyPayment * numberOfYears * 12;

    monthlyPayment = static_cast<int>(monthlyPayment * 100) / 100.0;
    totalPayment = static_cast<int>(totalPayment * 100) / 100.0;

    // Display result
    cout << "The monthly payment is " << monthlyPayment << endl <<
        "The total payment is " << totalPayment << endl;

    return 0;
}