#pragma GCC optimize("O3")
#include <bits/stdc++.h>
#define debug(...) ((void)0)

using namespace std;
using ll = long long;
using ld = long double;

void solve(int) {
    string A, B;
    cin >> A >> B;

    if (B.size() > A.size()) {
        cout << "No" << endl;
        return;
    }

    bool ok = true;

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

    for (int i = 0; i < (int)min(A.size(), B.size()); i++) {
        ok &= (A[i] >= B[i]);
    }

    cout << (ok ? "Yes" : "No") << endl;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    solve(0);
}