#include <iostream>
using namespace std;
int rasturnat(int n)
{
int r = 0;
while (n != 0)
{
r = r * 10 + n % 10;
n = n / 10;
}
return r;
}
int main()
{
int n, m, k, max = -1000000;
cin >> k >> m >> n;
if (rasturnat(k) > max)
{
max = rasturnat(k);
}
if (rasturnat(m) > max)
{
max = rasturnat(m);
}
if (rasturnat(n) > max)
{
max = rasturnat(n);
}
cout << max;
return 0;
}