#!/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
    num_lower = num_upper = num_digits = num_special = 0
    for c in password:
        if c in numbers:
            num_digits += 1
        elif c in lower_case:
            num_lower += 1
        elif c in upper_case:
            num_upper += 1
        elif c in special_characters:
            num_special += 1
    
    add = 0
    if num_digits == 0:
        add += 1
    if num_lower == 0:
        add += 1
    if num_upper == 0:
        add += 1
    if num_special == 0:
        add += 1
    
    if add+n < 6:
        add += 6-(add+n)
    
    return add
        
if __name__ == "__main__":
    n = int(input().strip())
    password = input().strip()
    answer = minimumNumber(n, password)
    print(answer)