import java.util.*;

public class Main {

    public static void main(String[] args) {

        int year;
        boolean isLeapYear = false;
        Scanner scan = new Scanner(System.in); // Initialize a Scanner with system InputStream
        System.out.println("----Program checking the leap year----");

        while (true) {
            System.out.println("Enter year: ");
            try {
                year = scan.nextInt(); // Wait to read user input to Integer/int
            } catch (Exception e) {
                scan.nextLine(); // use this to clear previous scan.next.. buffer
                continue;
            }

            if (year % 4 == 0) { // divisible 4 - leap year
                if (year % 100 == 0) { // divisible both 4 and 100 is not leap year
                    if (year % 400 == 0) // divisible 400 is leap year
                        isLeapYear = true;
                    else
                        isLeapYear = false; // not divisible 400 is not leap year
                } else { // divisible 4 but not divisible 100 - leap year
                    isLeapYear = true;
                }
            } else { // not leap year
                isLeapYear = false;
            }

            if (isLeapYear)
                System.out.println(year + " is a leap year.");
            else
                System.out.println(year + " isn't a leap year.");
        }
    }
}