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

string numbers = "0123456789";
string lower_case = "abcdefghijklmnopqrstuvwxyz";
string upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
string special_characters = "!@#$%^&*()-+";
    
int contains(string p, string a) {
    return p.find_first_of(a) == string::npos;
}

int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */
    int N;
    cin >> N;
    string p;
    cin >> p;
    int missing = contains(p, numbers) + contains(p, lower_case) + contains(p, upper_case) + contains(p, special_characters);
    if (N + missing < 6) {
        missing += 6 - N - missing;
    }
    cout << missing << endl;
    return 0;
}