#!/bin/python

import sys
numbers = set(list("0123456789"))
lower_case = set(list("abcdefghijklmnopqrstuvwxyz"))
upper_case = set(list("ABCDEFGHIJKLMNOPQRSTUVWXYZ"))
special = set(list("!@#$%^&*()-+"))
def minimumNumber(n, password):
    nu,l,u,s=0,0,0,0
    for i in numbers:
        if i in password:
            nu=1
    for i in lower_case:
        if i in password:
            l=1
    for i in upper_case:
        if i in password:
            u=1
    for i in special:
        if i in password:
            s=1
    p=password
    password=""
    if nu==0:
        password+="1"
    if l==0:
        password+="a"
    if u==0:
        password+="A"
    if s==0:
        password+="@"
    if len(p)+len(password)<6:
        password+="a"*(6-len(p)-len(password))
    return len(password)
if __name__ == "__main__":
    n = int(raw_input().strip())
    password = raw_input().strip()
    answer = minimumNumber(n, password)
    print answer