#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
#define pb push_back

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


int main(){
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    int n;
    cin >> n;
    for (int tt = 1; tt <= 1; tt++){
        string s;
        cin >> s;
        int kol1=0;
        int kol2=0;
        int kol3=0;
        int kol4=0;
        for (int i = 0; i < s.size(); i++){
            for (int j = 0; j < numbers.size(); j++){
                if (s[i] == numbers[j]){
                    kol1=1;
                    break;
                }
            }
            for (int j = 0; j < lower_case.size(); j++){
                if (s[i] == lower_case[j]){
                    kol2=1;
                    break;
                }
            }
            for (int j = 0; j < upper_case.size(); j++){
                if (s[i] == upper_case[j]){
                    kol3=1;
                    break;
                }
            }
            for (int j = 0; j < special_characters.size(); j++){
                if (s[i] == special_characters[j]){
                    kol4=1;
                    break;
                }
            }
        }
        int kek = 4 - (kol1+kol2+kol3+kol4);
        int ans = 1e9;
        if (s.size() < 6){
            ans = max(kek, 6-(int)s.size());
        } else
        ans = kek;
        cout << ans;
    }

}