using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
class Solution
{

    static int minimumNumber(int n, string password)
    {
        char[] numbers = ("0123456789").ToCharArray();
        char[] lower_case = "abcdefghijklmnopqrstuvwxyz".ToCharArray();
        var upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ".ToCharArray();
        var special_characters = "!@#$%^&*()-+".ToCharArray();
        var pass = password.ToCharArray();
        int count = 0;
        if (pass.Where(p => numbers.Contains(p)).Count() == 0)
            count++;
        if (pass.Where(p => lower_case.Contains(p)).Count() == 0)
            count++;
        if (pass.Where(p => upper_case.Contains(p)).Count() == 0)
            count++;
        if (pass.Where(p => special_characters.Contains(p)).Count() == 0)
            count++;
        if (n + count < 6)
            count += 6 - n - count;
        return count;
    }

    static void Main(String[] args)
    {
        int n = Convert.ToInt32(Console.ReadLine());
        string password = Console.ReadLine();
        int answer = minimumNumber(n, password);
        Console.WriteLine(answer);
    }
}