提示用户输入月份和年份，然后显示这个月的天数。

public class ExamDemo {

       public static void main(String[] args) {

              java.util.Scanner input = new java.util.Scanner(System.in);

              System.out.print("Enter a month in the year (e.g., 1 for Jan): ");

              int month = input.nextInt();

              System.out.print("Enter a year: ");

              int year = input.nextInt();

              int numberOfDaysInMonth = 0;

              switch (month) {

                     case 1:

                            System.out.print("January " + year);

                            numberOfDaysInMonth = 31;

                            break;

                     case 2:

                            System.out.print("February " + year);

                            if (year % 400 == 0 || (year % 4 == 0 && year % 100 != 0))

                                   numberOfDaysInMonth = 29;

                            else

                                   numberOfDaysInMonth = 28;

   &nb