#include <bits/stdc++.h>

using namespace std;

int minimumNumber(int n, string password) {
    bool lower = false, upper = false, number = false, special = false;
    string specialChars = "!@#$%^&*()-+";
    for(int i = 0; i < password.length(); i++){
        if(password[i] >= '0' && password[i] <= '9'){
            number = true;
        }
        if(password[i] >= 'a' && password[i] <= 'z'){
            lower = true;
        }
        if(password[i] >= 'A' && password[i] <= 'Z'){
            upper = true;
        }
        for(int j = 0; j < specialChars.length(); j++){
            if(password[i] == specialChars[j]){
                special = true;
                break;
            }
        }
    }
    int extraChar = !lower + !upper + !number + !special;
    return (n + extraChar >= 6 ? extraChar : 6 - n);
}

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