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

public class Solution {

    public static void main(String[] args) throws IOException {
        FastReader in = new FastReader();
        int n = in.nextInt();
        String pass = in.nextLine().trim();

        
        
        int cnt = 4;
        String numbers = "0123456789";
        String lower_case = "abcdefghijklmnopqrstuvwxyz";
        String upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
        String special_characters = "!@#$%^&*()-+";

        for (char c : pass.toCharArray()) {
            if (numbers.contains(c + "")) {
                cnt--;
                break;
            }
        }

        for (char c : pass.toCharArray()) {
            if (lower_case.contains(c + "")) {
                cnt--;
                break;
            }
        }

        for (char c : pass.toCharArray()) {
            if (upper_case.contains(c + "")) {
                cnt--;
                break;
            }
        }

        for (char c : pass.toCharArray()) {
            if (special_characters.contains(c + "")) {
                cnt--;
                break;
            }
        }

        if((n+cnt)<6){
            System.out.println(cnt +6-(n+cnt));
        }
        else System.out.println(cnt);

    }

    static class FastReader {

        BufferedReader br;
        StringTokenizer st;

        public FastReader() {
            br = new BufferedReader(new InputStreamReader(System.in));
        }

        String next() {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        int nextInt() {
            return Integer.parseInt(next());
        }

        long nextLong() {
            return Long.parseLong(next());
        }

        double nextDouble() {
            return Double.parseDouble(next());
        }

        String nextLine() {
            String str = "";
            try {
                str = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        }
    }
}