#include <iostream>
#include <string>
#include <algorithm>

using namespace std;

int main () {
    string A, B; cin >> A >> B;

    reverse(A.begin(), A.end());
    reverse(B.begin(), B.end());

    if (A.size() < B.size()) {
        cout << "No" << "\n";
        return 0;
    }

    bool ok = true;
    for (int i = 0; i < B.size(); i++) {
        if (A[i] < B[i]) ok = false;
    }

    if (ok) {
        cout << "Yes" << "\n";
    }
    else {
        cout << "No" << "\n";
    }
}