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

int main() {
  string A, B;
  cin >> A >> B;
  cout << ((A.at(0) * 100 + A.at(2) * 10 + A.at(4) >= B.at(0) * 100 + B.at(2) * 10 + B.at(4)) ? "YES" : "NO") << "\n";
}