#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#define endl '\n'
using namespace std;

typedef long long ll;

int main() {
	string s, t, tmp, tmp2;
	cin >> s >> t;
	if (s > t)
		cout << "No" << endl;
	else
		cout << "Yes" << endl;
	return 0;
}