#include <iostream>
#include <string>
using namespace std;

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

    for (int i = 0; i <= N - 3; i++) {
        if (S.substr(i, 3) == "404") {
            cout << "Found";
            return 0;
        }
    }

    cout << "NotFound";
    return 0;
}