numbers = set("0123456789")
lower_case = set("abcdefghijklmnopqrstuvwxyz")
upper_case = set("ABCDEFGHIJKLMNOPQRSTUVWXYZ")
special_characters = set("!@#$%^&*()-+")

input()
password = input().strip()

check = [True] * 4
for c in password:
    if c in numbers:
        check[0] = False
    elif c in lower_case:
        check[1] = False
    elif c in upper_case:
        check[2] = False
    elif c in special_characters:
        check[3] = False
        
ans = sum(check)
ans += max(6 - (len(password) + ans), 0)
print(ans)