#include <bits/stdc++.h>
using namespace std;
int main() {
  int a0, b0, c0;
  int a1, b1, c1;
  scanf("%d.%d.%d", &a0, &b0, &c0);
  scanf("%d.%d.%d", &a1, &b1, &c1);
  if (a0 < a1) { cout << "NO" << endl; exit(0); }
  else if (a0 > a1) { cout << "YES" << endl; exit(0); }
  if (b0 < b1) { cout << "NO" << endl; exit(0); }
  else if (b0 > b1) { cout << "YES" << endl; exit(0); }
  if (c0 < c1) { cout << "NO" << endl; exit(0); }
  cout << "YES" << endl;
  return 0;
}