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 isDigit = 1;
        int isLowercase = 1;
        int isUppercase = 1;
        int isSpecialChar = 1;
        
        char arr[] = password.toCharArray();
        String specials = "!@#$%^&*()-+";
        
        for(char ch : arr) {
            if(Character.isDigit(ch) && isDigit == 1) {
                isDigit = 0;
            } else if(Character.isUpperCase(ch) && isUppercase == 1) {
                isUppercase = 0;
            } else if(Character.isLowerCase(ch) && isLowercase == 1) {
                isLowercase = 0;
            } else if(specials.indexOf(ch) != -1 && isSpecialChar == 1) {
                isSpecialChar = 0;
            }
        }
        
        int sum = (isDigit + isLowercase + isUppercase + isSpecialChar);
        int len = n + sum;
        
        if(len >= 6) {
            return sum;
        }
        
        int needMore = 6 - len; 
        return sum + needMore;
        
    }

    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();
    }
}