#!/bin/python3

import sys
numbers = "0123456789"
lower_case = "abcdefghijklmnopqrstuvwxyz"
upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
special_characters = "!@#$%^&*()-+"
def minimumNumber(n, password):
    # Return the minimum number of characters to make the password strong
    add=0
    num=len(list(filter(lambda x:x in numbers,password)))
    lc=len(list(filter(lambda x:x in lower_case,password)))
    uc=len(list(filter(lambda x:x in upper_case,password)))
    sc=len(list(filter(lambda x:x in special_characters,password)))
    if num==0:
        add+=1
    if lc==0:
        add+=1
    if uc==0:
        add+=1
    if sc==0:
        add+=1
    if n+add<6:
        add=6-n
    return add

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