#include <iostream>
using namespace std;
int main()
{
int n, i, cif, cifmax;
long long num, rez=0;
cin >> n;
for (i=1; i<=n; ++i)
{
cin >> num;
cifmax=0;
while (num)
{
cif=num%10;
if (cif>cifmax) cifmax=cif;
num/=10;
}
rez=rez*10+cifmax;
}
rez*=rez;
cout << rez;
return 0;
}