#include<bits/stdc++.h>
using namespace std;
int main () {
	int a, b;
	cin >> a >> b;
	while (a + b) {
		if ((a % 10) < (b % 10)) {
			puts("No");
			return 0;
		}
		a /= 10;
		b /= 10;
	}
	puts("Yes");
}