#include <iostream>
using namespace std;
int m, n, a, b, c, d, cif1, cif2, nr;
int main()
{
cin >> m >> n;
a = m % 10;
b = m / 10;
c = n % 10;
d = n / 10;
if(a >= b) cif1 = a;
else cif1 = b;
if(c >= d) cif2 = c;
else cif2 = d;
if(cif1 >= cif2) nr = cif1 * 10 + cif2;
else nr = cif2 * 10 + cif1;
cout << nr;
return 0;
}