#!/bin/python3

import sys
import re


def minimumNumber(n, password):

    count = 4

    if re.search(r'\d', password, flags=0):
        count -= 1
    if re.search(r'[A-Z]', password, flags=0):
        count -= 1
    if re.search(r'[a-z]', password, flags=0):
        count -= 1
    if re.search(r'[!@#$%^&*()\-+]', password, flags=0):
        count -= 1

    char_needed = 6 - n

    if count > char_needed:
        return count
    else:
        return char_needed


if __name__ == "__main__":
    n = int(input().strip())
    password = input().strip()
    answer = minimumNumber(n, password)
    print(answer)