#include <bits/stdc++.h>

using namespace std;

string numbers = "0123456789";
string lower_case = "abcdefghijklmnopqrstuvwxyz";
string upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
string special_characters = "!@#$%^&*()-+";
    
int minimumNumber(int n, string password) {
    // Return the minimum number of characters to make the password strong
    if (n==0) return 6;
    
    int dig=1, caplc=1, capuc=1, sig=1;
    if (password.find_first_of(numbers)!=std::string::npos) dig=0;
    if (password.find_first_of(lower_case)!=std::string::npos) caplc=0;
    if (password.find_first_of(upper_case)!=std::string::npos) capuc=0;
    if (password.find_first_of(special_characters)!=std::string::npos) sig=0;
    
    int minNumber = dig+caplc+capuc+sig;
    int minlen = 6-password.length();
    if (password.length()<6 && minNumber < minlen) minNumber = minlen;
    return minNumber;
    
}

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