题解 | #获得月份天数#

import java.util.Scanner;
public class Main {
    
    public static void main(String[] args) {
        
        Scanner sc = new Scanner(System.in);
        while(sc.hasNext()) {
            int year = sc.nextInt();
            int month = sc.nextInt();
            switch(month) {
                case 1:    System.out.println(31);    break;
                case 2:    
                    if((year % 4 == 0 && year % 100 != 0 ) || year % 400 == 0) {
                        System.out.println(29);
                    } else {
                        System.out.println(28);
                    }
                    break;
                case 3:    System.out.println(31);    break;
                case 4:    System.out.println(30);    break;
                case 5:    System.out.println(31);    break;
                case 6:    System.out.println(30);    break;
                case 7:    System.out.println(31);    break;
                case 8:    System.out.println(31);    break;
                case 9:    System.out.println(30);    break;
                case 10:    System.out.println(31);    break;
                case 11:    System.out.println(30);    break;
                case 12:    System.out.println(31);    break;
            }
        }
    }
}