#include <iostream>
#include <fstream>

using namespace std;
ifstream f("cifra.in");
ofstream g("cifra.out");

int t,a,b,sum,s;
int main()
{
f>>t;

sum=1;
while(t>0)
{
    f>>a;
    b=a;
    while(b>0)
    {
        sum=sum*a;b--;
    }


t--;
    s=s+sum;


    cout<<sum%10;
}



    return 0;
}