#include <bits/stdc++.h>

using namespace std;

int main() {
    int a0, b0, c0, a1, b1, c1;
    char d1, d2, d3, d4;
    cin >> a0 >> d1 >> b0 >> d2 >> c0;
    cin >> a1 >> d3 >> b1 >> d4 >> c1;
    if ((a0 * 1000000 + b0 * 1000 + c0) >= (a1 * 1000000 + b1 * 1000 + c1)) {
        cout << "YES" << endl;
    } else {
        cout << "NO" << endl;
    }
    return 0;
}