import java.util.*;
public class Test {
    public static void main(String[] args) throws Throwable {
        Scanner sc = new Scanner(System.in);
        String buf;
        int year;
        GregorianCalendar c = new GregorianCalendar();
        while (true) {
            System.out.print("请输入年([yyyy]格式):");
            buf = sc.nextLine();
            try {
                year = Integer.parseInt(buf);
                if (year < 0) {throw new Exception("负数");}
                System.out.println(c.isLeapYear(year) ? "闰年" : "不是闰年");
                System.out.print("是否继续？(y/n):");
                buf = sc.nextLine();
                if ("y".equalsIgnoreCase(buf)) break;
            } catch (Exception e) {
                System.out.println("输入错误，请重输");
            }
        }
    }
}