import java.util.Scanner;

/**
 * Prompts the user for a month and indicates how many days are in that month.
 * 
 * @author pollen
 */
public class DaysInMonth {
    public static void main(String[] args) {
    
        Scanner in = new Scanner(System.in);
        System.out.print("Enter the number of a month (1-12): ");
        
        int month = in.nextInt();
        String msg = "error";
        
        switch (month) {
        case 1:
        case 3:
        case 5:
        case 7:
        case 8:
        case 10:
        case 12:
            msg = "31 days";
            break;
            
        case 2:
            msg = "28 days";
            break;
            
        case 4:
        case 6:
        case 9:
        case 11:
            msg = "30 days";
            break;
        }
        
        System.out.println(msg);
    }
}