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

int main(){
  int A,B;cin>>A>>B;
  
  if(B>A){
    cout<<"No"<<endl;
    return 0;
  }
  
  while(A!=0&&B!=0){
    if(A%10<B%10){
      cout<<"No"<<endl;
      return 0;
    }
    A/=10;
    B/=10;
  }
  cout<<"Yes"<<endl;
}