#!/bin/python3

import sys

def minimumNumber(n, password):
    # Return the minimum number of characters to make the password strong
    sp = "!@#$%^&*()-+"
    num = 0;
    n = 0;
    if(len(password) < 6):
        num = 6 - len(password)
    if(not any(c.isupper() for c in password)):
        n += 1
    if(not any(c.islower() for c in password)):
        n += 1
    if(not any(c.isdigit() for c in password)):
        n += 1
    if(not any((c in password) for c in sp)):
        n += 1
    
    if(n > num):
        return n
    else:
        return num

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