#!/bin/python3

import sys

def minimumNumber(n, password):
    numbers = "0123456789"
    lower_case = "abcdefghijklmnopqrstuvwxyz"
    upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    special_characters = "!@#$%^&*()-+"
    
    p = list(password)
    if n==0:
        return 6
    
    d = 0
    u = 0
    l = 0
    s = 0
    
    for c in p:
        if c in list(upper_case):
            u = 1
        elif c in list(lower_case):
            l = 1
        elif c.isdigit():
            d = 1
        elif c in list(special_characters):
            s = 1
    
    count = 0  
    if d==0:
        count = count+1
    if u==0:
        count = count+1
    if l==0:
        count = count+1
    if s==0:
        count = count+1

    if n+count < 6:
        return 6-n
    
    return count
            
if __name__ == "__main__":
    n = int(input().strip())
    password = input().strip()
    answer = minimumNumber(n, password)
    print(answer)