#!/bin/python3

import sys

def minimumNumber(n, password):
    # Return the minimum number of characters to make the password strong
    lower_case = False
    upper_case = False
    digit = False
    special = False
    for c in list(password):
        if c in list("abcdefghijklmnopqrstuvwxyz"):
            lower_case = True
        if c in list("ABCDEFGHIJKLMNOPQRSTUVWXYZ"):
            upper_case = True
        if c in list("0123456789"):
            digit = True
        if c in list("!@#$%^&*()-+"):
            special = True
    extra = 0
    if not lower_case:
        extra += 1
    if not upper_case:
        extra += 1
    if not digit:
        extra += 1
    if not special:
        extra += 1
    if n + extra < 6:
        return_val = (6 - n - extra) + extra
    else:
        return_val = extra
    return return_val

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