#include <bits/stdc++.h>

using namespace std;

int minimumNumber(int n, string password) {
    // Return the minimum number of characters to make the password strong
    string numbers = "0123456789";
    string lower_case = "abcdefghijklmnopqrstuvwxyz";
    string upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    string special_characters = "!@#$%^&*()-+";

    bool num = false, lo = false, up = false, sp = false;
    for(int i = 0; i < password.length(); i++) {
        if(isdigit(password[i])) {
            size_t found = numbers.find((password[i]));
            if(found != string::npos)
                num = true;
        }
        else if(isalpha(password[i])) {
            size_t found = lower_case.find((password[i]));
            if(found != string::npos)
                lo = true;

            found = upper_case.find((password[i]));
            if(found != string::npos)
                up = true;
        }
        else {
            size_t found = special_characters.find((password[i]));
            if(found != string::npos)
                sp = true;
        }
    }

   // cout<<num<<lo<<up<<sp<<endl;
    int na = 0;

    if(!num)
        na++;
    if(!lo)
        na++;
    if(!up)
        na++;
    if(!sp)
        na++;

    if((na + n) < 6) {
        int res = 6 - (n);
        return res;
    }
    else
        return na;


}

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