#include <bits/stdc++.h>
using namespace std;
constexpr int inf = 1073741823;
constexpr long long linf = 0xfffffffffffffff;
using ll = long long;
using ld = long double;

int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    int n; cin >> n;
    string s; cin >> s;
    bool f = true;
    for(int i = 0; i < n - 2; i++) {
        if(s[i] == '4' && s[i + 1] == '0' && s[i + 2] == '4') f = false;
    }
    if(!f) {
        cout << "Found" << endl;
    }else {
        cout << "NotFound" << endl;
    }
}