#include <fstream>

using namespace std;

ifstream fin ( "cifra.in");
ofstream fout ("cifra.out");

int main()
{
    int n,k,i,s=0,j,p,l,put;
    fin>>n;
    for ( p=0;p<n;p++)
    {
        fin>>j;
        s=0;
        for(i=1;i<=j;i++)
        {
            k=i%10;
            put=1;
            for(l=1;l<=i;l++)
            {
                put=put*k;
                put=put%10;

            }

            s=s+put;
            s=s%10;
        }
        fout<<s<<"\n";
    }
    fin.close();
    fout.close();
    return 0;
}