import java.io.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class Solution
{
    public static void main(String[] args) throws IOException
    {

        BufferedReader br=new BufferedReader(new InputStreamReader(System.in));

        int n=Integer.parseInt(br.readLine());

        String pwd=br.readLine();

        int count=0;

        String regEx1 = "([A-Z]+)";
        String regEx2= "([0-9]+)";
        String regEx3= "([a-z]+)";
        String regEx4="([!@#\\$%\\^&\\*\\(\\)\\-\\+]+)";


        Pattern pattern = Pattern.compile(regEx1);
        Matcher matcher = pattern.matcher(pwd);

        if(!matcher.find())count++;

        pattern=Pattern.compile(regEx2);
        matcher=pattern.matcher(pwd);

        if(!matcher.find())count++;

        pattern=Pattern.compile(regEx3);
        matcher=pattern.matcher(pwd);

        if(!matcher.find())count++;

        pattern=Pattern.compile(regEx4);
        matcher=pattern.matcher(pwd);

        if(!matcher.find())count++;

        if(pwd.length()>6)
            System.out.println(count);

        else if((6-pwd.length())>count)
            System.out.println(6-pwd.length());

        else
            System.out.println(count);




        }

    }