x=int(input("enter month number:"))
match x:
    case x if x in(1,3,5,7,8,10,12):
        print("31 days")
    case x if x in(4,6,9,11):
        print("30 days")
    case 2:
        print("28 or 29 days")
    case _:
        print("invalid month number")
print()
