#include <stdio.h>
#include <bits/stdc++.h>
#include <atcoder/all>
using namespace atcoder;
using mint = modint998244353;
using namespace std;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf32 1000000001
#define Inf64 1000000000000000001

int main(){
	
	long long a,b;
	cin>>a>>b;
	while(a!=0 || b!=0){
		int x = a%10,y = b%10;
		a/= 10,b/=10;
		if(x<y){
			cout<<"No"<<endl;
			return 0;
		}
	}
	cout<<"Yes"<<endl;
	
    return 0;
}