#include <bits/stdc++.h>

using i64 = long long;

int main() {

    std::cin.tie(nullptr)->sync_with_stdio(false);

    
    std::string a, b;
    std::cin >> a >> b;

    if (a.size() < b.size()) {
        std::cout << "No\n";
        return 0;
    }
    std::reverse(a.begin(), a.end());
    std::reverse(b.begin(), b.end());
    for (int i = 0; i < std::min(a.size(), b.size()); ++i) {
        // std::cout << "i = " << i << " " << a[i] << " " << b[i] << '\n';
        // std::cout << "ck is : " << (a[i] < b[i]) << '\n';
        if (a[i] < b[i]) {
            std::cout << "No\n";
            return 0;
        }
    }

    std::cout << "Yes\n";

    return 0;
}