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

int main() {
    int n; cin >> n;
    string s; cin >> s;
    
    int u = 0, l = 0, sp = 0, d = 0;
    
    for (int i = 0; i < n; ++i) {
        if (isdigit(s[i]))  ++d;
        else if (isupper(s[i]))  ++u;
        else if (islower(s[i]))  ++l;
        else    ++sp;
    }
    int e = 0;
    if (!u) ++u, ++e;
    if (!l) ++l, ++e;
    if (!sp) ++sp, ++e;
    if (!d) ++d, ++e;
    if (n + e < 6)  e += 6 - n - e;
        
    cout << e << endl;
    return 0;
}