#include <bits/stdc++.h>

using namespace std;

int minimumNumber(int n, string password) {
    //numbers = "0123456789"
    //lower_case = "abcdefghijklmnopqrstuvwxyz"
    //upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    //special_characters = "!@#$%^&*()-+"
    bool digit = false, lower = false, upper = false, special = false;
    int sz = password.size();
    for(int i = 0; i < sz; i++)
    {
        int cc = password[i];
        char c = password[i];
        if (!digit && cc >= 48 && cc < 58)
            digit = true;
        if (!lower && cc >= 97 && cc < 123)
            lower = true;
        if (!upper && cc >= 65 && cc < 91)
            upper = true;
        if (!special && ( c == '!' || c == '@' || c == '#' || c == '$' || c == '%' || c == '^' || c == '&' || c == '*' || c == '(' || c == ')' || c == '-' || c == '+'))
            special = true;
    }
    int initial = 0;
    if (!digit)
    {
        initial++;
    }if (!lower)
    {
        initial++;
    }if (!upper)
    {
        initial++;
    }if (!special)
    {
        initial++;
    }
    if (sz + initial < 6)
        return 6-sz;
    return initial;
    // Return the minimum number of characters to make the password strong
}

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