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

     static int minimumNumber(int n, string password)
    {
        List<char> special_characters = new List<char>() { '!', '@', '#', '$', '%', '^', '&', '*', '(', ')', '-', '+' };
      
        int final = 0;
        if (!password.Any(char.IsLower))
            final++;

        if (!password.Any(char.IsUpper))
            final++;
        if (!password.Any(char.IsDigit))
            final++;
        if (!password.Any(special_characters.Contains))
            final++;

     
        if (password.Length < 6)
        {
            if (final < (6 - n))
                final = 6 - n;
        }
    
        return final;
    }                         

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