#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
#include <string>
using namespace std;

const string numbers = "0123456789";
const string lower_case = "abcdefghijklmnopqrstuvwxyz";
const string upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
const string special_characters = "!@#$%^&*()-+";

bool contains(const string &s, const string &p) {
        for (auto c : s)
                if (p.find(c) != string::npos)
                        return true;
        return false;
}

int solve(const string &pw) {
        int ans = 0;
        if (!contains(pw, numbers))
                ++ans;
        if (!contains(pw, lower_case))
                ++ans;
        if (!contains(pw, upper_case))
                ++ans;
        if (!contains(pw, special_characters))
                ++ans;
        if (pw.size() + ans < 6)
                return 6 - pw.size();
        return ans;
}

int main(void) {
        cout.sync_with_stdio(false);
        int n;
        string pw;
        cin >> n >> pw;
        cout << solve(pw) << endl;
        return 0;
}