#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<int,int> P;
#define REP(i,n) for(int i=0;i<int(n);i++)






int main(){
	cin.tie(nullptr);  ios_base::sync_with_stdio(false);
    int i,j,k;


    string A,B;
    cin >> A >> B;

    int n=A.size(),m=B.size();

    if(m>n){
    	cout << "No" << endl;
    	return 0;
    }

    reverse(A.begin(),A.end());
    reverse(B.begin(),B.end());

    REP(i,m){
    	if(B[i]>A[i]){
        	cout << "No" << endl;
        	return 0;
    	}
    }


    cout << "Yes" << endl;




	return 0;

}