#include <bits/stdc++.h>
#define FOR(i,a,b) for(int i = (a); i < (b); ++i)
#define REP(i,n) FOR(i,0,n)
#define sz(n) (int)(n).size()
using namespace std;
typedef long long ll;
typedef vector<int> VI;

int main() {
	string s1, s2;
	int t1[3];
	char t;
	cin >> t1[0] >> t >> t1[1] >> t >> t1[2];
	REP(i, 3) s1 += t1[i];
	cin >> t1[0] >> t >> t1[1] >> t >> t1[2];
	REP(i, 3) s2 += t1[i];
	if (s1 >= s2) {
		cout << "YES" << endl;
		return 0;
	}
	cout << "NO" << endl;
	return 0;
}