#include <iostream>
#include <string>

using namespace std;

int main () {
    int N; cin >> N;
    string S; cin >> S;

    bool ok = false;
    for (int i = 0; i < N - 2; i++) {
        if (S.substr(i, 3) == "404") ok = true;
    }

    if (ok) {
        cout << "Found" << "\n";
    }
    else {
        cout << "NotFound" << "\n";
    }
}