#include <bits/stdc++.h>
#define FOR(i, a, b) for (int i = a; i<=b ; i++)
#define FORD(i, a, b) for (int i = a; i>=b; i--)
#define REP(i, a) for (int i = 0; i<a; i++)
#define N 100100
#define pp pair<int, int>
#define IO ios::sync_with_stdio(false); cin.tie(NULL);cout.tie(NULL);

using namespace std;
int n;
string st;

int main() {
    IO;
    cin>>n>>st;
    string ss = "!@#$%^&*()-+";
    bool number = false, low = false, up = false, spe = false;
    int cnt = 0;
    for (char c : st) {
        int idx = c - '0';
        if (0 <= idx && idx < 10) {
            if (!number) cnt++;
            number = true;
        }
        idx = c - 'a';
        if (0 <= idx && idx < 26) {
            if (!low) cnt++;
            low = true;
        }
        idx = c - 'A';
        if (0 <= idx && idx < 26) {
            if (!up) cnt++;
            up = true;
        }
        if (ss.find(c) != -1) {
            if (!spe) cnt++;
            spe = true;
        }
    }
    int ans = 4 - cnt;
    if (ans + n < 6) {
        ans = 6 - n;
        cout<<ans;
    } else cout<<ans;
}