#include <bits/stdc++.h>

using namespace std;

int minimumNumber(int n, string password)
{
    string numbers = "0123456789";
    string lower_case = "abcdefghijklmnopqrstuvwxyz";
    string upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    string special = "!@#$%^&*()-+";
    
    int ans = 4;
    
    for (int i = 0; i < 10; i++)
        if (password.find(numbers[i]) != string::npos)
        {
            ans--;
            break;
        }
    
    for (int i = 0; i < 26; i++)
        if (password.find(lower_case[i]) != string::npos)
        {
            ans--;
            break;
        }
    
    for (int i = 0; i < 26; i++)
        if (password.find(upper_case[i]) != string::npos)
        {
            ans--;
            break;
        }
    
    for (int i = 0; i < 12; i++)
        if (password.find(special[i]) != string::npos)
        {
            ans--;
            break;
        }
    
    return max(6-n, ans);
}

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