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

int main() {
    int n;
    string s;
    cin >> n >> s;
    for (int i = 0; i + 2 < n; i++) {
        if (s.substr(i, 3) == "404") {
            cout << "Found" << endl;
            return 0;
        }
    }
    cout << "NotFound" << endl;
}