#include <bits/stdc++.h>

using namespace std;

int minimumNumber(int n, string password) {
    // Return the minimum number of characters to make the password strong
    int s=1,c=1,sy=1,d=1;
    
    for(int i=0;password[i];i++)
    {
        if(password[i] >= 'a' && password[i] <='z')
            s=0;
        else if(password[i] >= 'A' && password[i] <='Z')
            c=0;
        else if((password[i] >= '0' && password[i] <='9'))
            d=0;
        else if(password[i] == '!' || password[i] <='@' || password[i] <='#' || password[i] <='$' || password[i] <='%' || password[i] <='^' || password[i] <='&' || password[i] <='*' || password[i] <='(' || password[i] <=')' || password[i] <='+' || password[i] <='-')
                sy=0;
    
    }
    
    s = s + d + c + sy;
    
    if(password.length() + s >= 6)
        return s;
    else
        return 6 - password.length();
    
}

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