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

public class Solution {

    static int minimumNumber(int n, String password) {
  char[] numbers = "0123456789".toCharArray();
 char[] lower_case = "abcdefghijklmnopqrstuvwxyz".toCharArray();
 char[] upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ".toCharArray();
 char[] special_characters = "!@#$%^&*()-+".toCharArray();
        int numminCount=1;
        int lcminCount=1;
        int ucminCount=1;
        int scminCount=1;
        
        for(char c :numbers)
        {                 
            long count = password.chars().filter(ch -> ch == c).count();
            if(count>0)
            {
                numminCount=0;
               break;
            }
        }
        
                for(char c :lower_case)
        {                 
            long count = password.chars().filter(ch -> ch == c).count();
        if(count>0)
            {
                lcminCount=0;
               break;
            }       
                }
        
                for(char c :upper_case)
        {                 
            long count = password.chars().filter(ch -> ch == c).count();
          if(count>0)
            {
                ucminCount=0;
               break;
            }       }
        
                for(char c :special_characters)
        {                 
            long count = password.chars().filter(ch -> ch == c).count();
      if(count>0)
            {
                scminCount=0;
               break;
            }       }
        int total=scminCount+ucminCount+lcminCount+numminCount;
        if((total+n) < 6)
        {
            total = total + (6 - (total+n));
        }
        return total;
    }

    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();
    }
}