#!/bin/python3

import sys

numbers = "0123456789"
lower_case = "abcdefghijklmnopqrstuvwxyz"
upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
special_characters = "!@#$%^&*()-+"

def minimumNumber(n, password):
    s = 0
    s += int(not any(s in numbers for s in password))
    s += int(not any(s in lower_case for s in password))
    s += int(not any(s in upper_case for s in password))
    s += int(not any(s in special_characters for s in password))
    if n < 6:
        return max(6-n, s)
    return s
if __name__ == "__main__":
    n = int(input().strip())
    password = input().strip()
    answer = minimumNumber(n, password)
    print(answer)