#include <iostream>
#include <cassert>
using namespace std;
using ll = long long;
template<class T> inline bool chmax(T& a, const T& b) {if (a<b) {a=b; return true;} return false;}
template<class T> inline bool chmin(T& a, const T& b) {if (b<a) {a=b; return true;} return false;}
const int INTINF = 1000001000;
const int INTMAX = 2147483647;
const ll LLMAX = 9223372036854775807;
const ll LLINF = 1000000000000000000;

int main() {
  ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
  ll A, B; cin >> A >> B;
  while (max(A,B) > 0) {
    if (A%10 < B%10) {
      cout << "No\n";
      return 0;
    }

    A/=10;
    B/=10;
  }
  cout << "Yes\n";
  return 0;
}