#!/bin/python3

import sys
import re

def minimumNumber(n, password):
    number = 0
    if re.search('[a-z]', password) is None:
        number += 1
    if re.search('[A-Z]', password) is None:
        number += 1
    if re.search('[!@#$%^&*()\-+]', password) is None:
        number += 1
    if re.search('\d', password) is None:
        number += 1
    
    if len(password) - 6 >= 0 or len(password) + number >=6:
        return number
    else:
        return max(number, 6 - len(password))


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