#include <bits/stdc++.h>

using namespace std;

string special = "!@#$%^&*()-+";

int minimumNumber(int n, string p) {
    int ans = 0;
    for (auto c : p) {
        if ('a' <= c && c <= 'z') {
            ans++; break;
        }
    }
    for (auto c : p) {
        if ('0' <= c && c <= '9') {
            ans++; break;
        }
    }
    for (auto c : p) {
        if ('A' <= c && c <= 'Z') {
            ans++; break;
        }
    }
    for (auto c : p) {
        bool yes = false;
        for (auto x : special)
            if (x == c) {
                yes = true;
                break;
            }
        if (yes) {
            ans++; break;
        }
    }
    return (4 - ans) + (4-ans+p.length() >= 6 ? 0 : 2 + ans - p.length());
}

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