#include <bits/stdc++.h>

using namespace std;

const string numbers = "0123456789";
const string lower_case = "abcdefghijklmnopqrstuvwxyz";
const string upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
const string special_characters = "!@#$%^&*()-+";

int minimumNumber(int n, string password) {
    // Return the minimum number of characters to make the password strong
    int result = 4;
    bool numberContains = false;
    bool upperContains = false;
    bool lowerContains = false;
    bool specialContains = false;
    for (int i = 0;i < password.size ();++i){
        if (!numberContains && numbers.find (password [i]) != string::npos){
            numberContains = true;
            result--;
        }
        else if (!lowerContains && lower_case.find (password [i]) != string::npos){
            lowerContains = true;
            result--;
        } else if (!upperContains && upper_case.find (password [i]) != string::npos){
            upperContains = true;
            result--;
        }else if (!specialContains && special_characters.find (password [i]) != string::npos){
            specialContains = true;
            result--;
        }           
    }
    if (password.size () + result < 6){
        result += 6 - password.size () - result;
    }
    return result;
}

int main() {
    int n;
    cin >> n;
    string password;
    cin >> password;
    int answer = minimumNumber(n, password);
    cout << answer << endl;
    return 0;
}