#!/bin/python3

import sys

def minimumNumber(n, password):
    numbers = "0123456789"
    lower_case = "abcdefghijklmnopqrstuvwxyz"
    upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    special_characters = "!@#$%^&*()-+"
    num=1
    l=1
    u=1
    s=1
    for x in password:
        if x in numbers:
            num=0
        elif x in lower_case:
            l=0
        elif x in upper_case:
            u=0
        elif x in special_characters:
            s=0
    res=num+l+u+s
    if (n+res)<6:
        res=6-n
    return res

if __name__ == "__main__":
    n = int(input().strip())
    password = input().strip()
    answer = minimumNumber(n, password)
    print(answer)