#include <bits/stdc++.h>

int main(){
    std::cin.tie(nullptr);
    std::ios::sync_with_stdio(false);

    int N;
    std::cin >> N;

    std::string S;
    std::cin >> S;

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

    if(found){
        std::cout << "Found" << std::endl;
    }else{
        std::cout << "NotFound" << std::endl;
    }
}