#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 i = 0;
    char c;
    bool lower = false;
    bool upper = false;
    bool number = false;
    bool special = false;
    
    int ret = 0;
    
    for (i = 0; i < password.length(); i++)
    {
        c = password.at(i);
        if (c >= 'a' && c <= 'z')
            lower = true;
        else if (c >= 'A' && c <= 'Z')
            upper = true;
        else if (c >= '0' && c <= '9')
            number = true;
        else if (c == '!' || c == '@' || c == '#' || c == '$' || c == '%' || c == '^' || c == '&' || c == '*' || c == '(' || c == ')' || c == '-' || c == '+')
            special = true;
    }
    
    if (lower == false)
        ret++;
    if (upper == false)
        ret++;
    if (number == false)
        ret++;
    if (special == false)
        ret++;
    
    if (n + ret < 6)
    {
        ret += 6 - n - ret;
    }
    return ret;
}

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