#include <bits/stdc++.h>
using namespace std;

string special = "!@#$%^&*()-+";

int main() {
    int ans = 0;
    int n; cin >> n;
    string s; cin >> s;
    int len = s.size();
    set<char> spe;
    for(char c: special) {
        spe.insert(c);
    }
    bool dig = false, up = false, low = false, sp = false;
    for(int i = 0; i < n; i++) {
        if(isdigit(s[i])) {
            dig = true;
        } else if(islower(s[i])) {
            low = true;
        } else if(isupper(s[i])) {
            up = true;
        } else if(spe.find(s[i]) != spe.end()) {
            sp = true;
        }
    }
    if(not up)
        ans++;
    if(not low) 
        ans++;
    if(not sp)
        ans++;
    if(not dig)
        ans++;
    if(len + ans < 6) {
        ans = 6 - len;
    }
    cout << ans << endl;
    return 0;
}