题解 | #获得月份天数#

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