#!/bin/python

import sys

def minimumNumber(n, password):
    count = 0
    numb = 0
    lower = 0
    upper = 0
    character = 0
    numbers = "0123456789"
    lower_case = "abcdefghijklmnopqrstuvwxyz"
    upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    special_characters = "!@#$%^&*()-+"
    for i in password:
        for j in numbers:
            if(i == j):
                numb = numb + 1
                break
        for k in lower_case:
            if(i == k):
                lower = lower +1
                break
        for l in upper_case:
            if(i == l):
                upper = upper + 1
                break
        for m in special_characters:
            if(i == m):
                character = character + 1
                break
    if(numb > 0):
        count = count + 0
    else:
        count = count + 1
    if(lower > 0):
        count = count + 0
    else:
        count = count + 1
    if(upper >0):
        count = count + 0
    else:
        count = count + 1
    if(character > 0):
        count = count + 0
    else:
        count = count + 1
    n = n + count
    if(n<6):
        count = count + (6-n)
            
            
    # Return the minimum number of characters to make the password strong
    return count
    
if __name__ == "__main__":
    
    n = int(raw_input().strip())
    password = raw_input().strip()
    answer = minimumNumber(n, password)
    print answer