#include <bits/stdc++.h>

using namespace std;

int main() {
    int a0, b0, c0, a1, b1, c1;
    char Deli;

    cin >> a0 >> Deli >> b0 >> Deli >> c0;
    cin >> a1 >> Deli >> b1 >> Deli >> c1;

    int x0 = a0 * 1000000 + b0 * 1000 + c0;
    int x1 = a1 * 1000000 + b1 * 1000 + c1;

    if (x1 <= x0) {
        cout << "YES" << endl;
    } else {
        cout << "NO" << endl;
    }
    return 0;
}