import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {
    
    static String numbers = "0123456789";
    static String lower_case = "abcdefghijklmnopqrstuvwxyz";
    static String upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    static String special_characters = "!@#$%^&*()-+";
    
    static int minimumNumber(int n, String password) 
    {
        int num = 0;
        if(!contains(numbers,password))
        {
            num++;
            n++;
        }
        if(!contains(lower_case,password))
        {
            num++;
            n++;
        }
        if(!contains(upper_case,password))
        {
            num++;
            n++;
        }
            
        if(!contains(special_characters,password))
        {
            num++;
            n++;
        }
        if(n < 6)
            num += (6 - n);
        return num;
    }
    static boolean contains(String s,String p)
    {
        for(int i = 0; i < p.length(); i++)
            for(int j = 0; j < s.length(); j++)
                if(p.charAt(i) == s.charAt(j))
                    return true;
            return false;
    }

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int n = in.nextInt();
        String password = in.next();
        int answer = minimumNumber(n, password);
        System.out.println(answer);
        in.close();
    }
}