#include <iostream>
#include <cmath>
#include <string>

using namespace std;

int main() {
    int A, B;
    int m, a, b;
    int d = 1;

    cin >> A >> B;
    for (d = 1, m = max(A, B); m/d >= 10; d*=10) {}
    while (d >= 1) {
        if ((A / d) != (B / d)) {
            a = (A / d) % 10;
            b = (B / d) % 10;
            if (((a*b==28)?(-1):1)*(a-b) > 0) {
                cout << A << endl;
            } else {
                cout << B << endl;
            }
            return 0;
        }
        d /= 10;
    };

    cout << A << endl;
    return 0;
}