#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 chk(string s, string chk)
{
    for(int i = 0 ; i < s.length() ; i++)
    {
        for(int j = 0 ; j < chk.length() ; j++)
        {
            if(s[i] == chk[j])
                return 0;
        }
    }
    
    return 1;
}

int main() 
{
    int n;
    cin >> n;
    
    string s;
    cin >> s;

    {
        int ans = 0;
        ans = chk(s, numbers) + chk(s, lower_case) + chk(s, upper_case) + chk(s, special_characters);
        
        if(n >= 6)
        cout << ans;
        
        else
        {
            int add = 6 - n;
            
            if(add > ans)
                cout << add ;
            
            else
                cout << ans;
        }
    }

    return 0;
}