#include <algorithm>
#include <cctype>
#include <cstring>
#include <iostream>
#include <string>

using namespace std;

int main()
{
    size_t n;
    cin >> n;
    string s;
    cin >> s;
    const char specials[] = "!@#$%^&*()-+";
    size_t lower = 0, upper = 0, digit = 0, special = 0;
    for (auto c : s) {
        digit += !!isdigit(c);
        lower += !!islower(c);
        upper += !!isupper(c);
        special += strchr(specials, c) != nullptr;
    }
    size_t res = 0;
    res += ((digit == 0) + (lower == 0) + (upper == 0) + (special == 0));
    
    cout << max((n <= 6 ? 6 - n : 0), res) << '\n';
}