#include <bits/stdc++.h>
#define REP(a,b,c) for(int a=b; a<(int)c; a++)
#define REPD(a,b,c) for(int a=b; a>(int)c; a--)
#define rep(a,b) REP(a,0,b)
#define repd(a,b) REPD(a,b,0)
typedef long long int ll;
using namespace std;

int main(){
  string A,B;
  cin >> A >> B;
  if(A >= B) cout << "YES" << endl;
  else cout << "NO" << endl;
  return 0;
}