Расчет кредита с вариантами

import java.util.*;
 
public class Main
{
    
 
    public static void main(String[] args)
 
    {
 
        Scanner keyboard = new Scanner(System.in);
        int loanAmount, loanDurationYears;
        double interestRate, monthlyPayment, totalInterest;
 
        System.out.print("Введіть суму кредиту:");
        loanAmount = keyboard.nextInt();
 
        System.out.print("Введіть срок кредиту(років):");
        loanDurationYears = keyboard.nextInt();
 
        System.out.print("Введіть відсоток кредитування:");
        interestRate = keyboard.nextDouble();
        keyboard.close();
 
        System.out.println("Сума кредиту:" + loanAmount + " грош. од");
        System.out.println("Тривалісь кредиту: " + loanDurationYears + " років");
        System.out.println("Відсоткова ставка: " + interestRate + "%");
 
        monthlyPayment = payment(loanAmount, loanDurationYears, interestRate);
        totalInterest = ((monthlyPayment * (loanDurationYears*12))-loanAmount);
        printTotals(loanAmount, loanDurationYears, interestRate, monthlyPayment, totalInterest);
    }
    public static double payment(int loanAmount, int loanDurationYears, double interestRate)
    {
        int a = loanAmount;
        int n = (loanDurationYears*12);
        double i = ((interestRate*.01)/12);
        double monthlyPayment = a*(Math.pow((1+i),n)*i)/((Math.pow((1+i),n))-1);
        return monthlyPayment;
 
 
    }
    public static void printTotals(int loanAmount, int loanDurationYears, double interestRate, double monthlyPayment, double totalInterest)
    {
 
        System.out.println("За " + loanDurationYears + " років кредиту на " + loanAmount + " грош. од. під " + interestRate + "%:");
        System.out.printf("Місячна плата = "+ "%.2f", monthlyPayment, "грош. од.");
        System.out.println();
        System.out.printf("Відсоток в грош. од. = "+ "%.2f", totalInterest);
        System.out.println();
 
    }}