#include <iostream>
#include<fstream>
using namespace std;
ifstream f("cifra.in");
ofstream g("cifra.out");
int main()
{int t,n;
f>>t;
int c,C,i,cif;
while(t--)
    {f>>n;C=0;
     while(n>=2)
        {
          i=n;
          c=i%10;
          cif=i%10;
          while(i>=2&&c!=0)
               {c=(c*cif)%10;
                i--;
               }
          n--;
          C+=c;
        }
    g<<(C+1)%10<<'\n';
    }
return 0;
}