#include using namespace std; string a[4] = {"0123456789", "abcdefghijklmnopqrstuvwxyz", "ABCDEFGHIJKLMNOPQRSTUVWXYZ", "!@#$%^&*()-+"}; int v[300]; bool vis[10] = {false}; int main() { int n; string str; cin >> n >> str; for (int i = 0; i < 4; ++i) for (auto c : a[i]) v[c] = i; for (int i = 0; i < n; ++i) vis[v[str[i]]] = true; int ans = 0; for (int i = 0; i < 4; ++i) ans += !vis[i]; ans = max(ans, 6-n); cout << ans << endl; }