import java.io.*;
import java.util.*;

/**
 *  
 * @author akashvermaofskt
 * Coding is love <3!
 */

class Stron {
    static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    static BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
    static StringTokenizer st = null;
    
    static String next() {
        while (st == null || !st.hasMoreElements()) {
            try {
                st = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return st.nextToken();
    }
    
    static int nextInt() {
        return Integer.parseInt(next());
    }
    
    static long nextLong() {
        return Long.parseLong(next());
    }

    public static void main(String args[]) {
        try {
            int n=nextInt();
            String pwd=next();
            
            HashMap<Character,Integer> map=new HashMap<>();
            
            for (int i = 0; i < pwd.length(); i++) {
                map.put(pwd.charAt(i), 1);
            }
            
            String numbers = "0123456789";
            String lower_case = "abcdefghijklmnopqrstuvwxyz";
            String upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
            String sc = "!@#$%^&*()-+";
            
            int ans=0;
            
            
            int flag=0;
            for (int i = 0; i < numbers.length(); i++) {
                if(map.containsKey(numbers.charAt(i)))flag=1;
            }

            if(flag==0)ans++;

            flag=0;
            for (int i = 0; i < lower_case.length(); i++) {
                if(map.containsKey(lower_case.charAt(i)))flag=1;
            }

            if(flag==0)ans++;

            flag=0;
            for (int i = 0; i < upper_case.length(); i++) {
                if(map.containsKey(upper_case.charAt(i)))flag=1;
            }

            if(flag==0)ans++;

            flag=0;
            for (int i = 0; i < sc.length(); i++) {
                if(map.containsKey(sc.charAt(i)))flag=1;
            }

            if(flag==0)ans++;
            
            if(pwd.length()+ans<6){
                ans+=6-(pwd.length()+ans);
            }
            
            
            bw.write(ans+"\n");
            bw.flush();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}