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) {
        int count = 0;
        boolean hasSpecial = false;
        boolean hasLower = false;
        boolean hasUpper = false;
        boolean isNumber = false;


        int minLength = 6;

        char[] special =   new String("!@#$%^&*()-+").toCharArray();
        Set<Character> set = new HashSet<>();

        for (char ch : special) {
            set.add(ch);
        }

        for (Character inCh : password.toCharArray()) {
            if (!hasUpper && Character.isUpperCase(inCh)) {
               hasUpper = true;
               count++;
            }

            if (!hasLower && Character.isLowerCase(inCh)) {
                hasLower = true;
                count++;
            }

            if (!hasSpecial && set.contains(inCh)) {
                hasSpecial = true;
                count++;
            }

            if (!isNumber && Character.isDigit(inCh)) {
                isNumber = true;
                count++;
            }

            if (count >= minLength) {
               return 0;
            }
        }

        int needToAdd = 0;

        if (!hasUpper) {
            needToAdd++;
        }

        if (!hasLower) {
            needToAdd++;
        }

        if (!hasSpecial) {
            needToAdd++;
        }

        if (!isNumber) {
            needToAdd++;
        }

        if (n + needToAdd < minLength) {
            needToAdd += minLength - (n + needToAdd);
        }
        
        return needToAdd;
    }

    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();
    }
}