// 20:51
#include<fstream>
using namespace std;

char t[106];
long nr,T,i;
long REZ[105];
long pow ( long nr )
{
    long x,rez=1;
    for ( x=1; x<=nr; ++x )
    {
        rez*=(nr%10);
        rez%=10;
    }
    return rez;
}
int main()
{
    for ( i=1; i<=100; ++i)
    {
        REZ[i]=REZ[i-1];
        REZ[i]+=pow(i);
        REZ[i]%=10;
    }

    ifstream in("cifra.in");
    ofstream out("cifra.out");
    in>>T;
    in.getline(t,105);
    for ( ; T; --T )
    {

        in.getline(t,105);
        nr=0;
        if ( strlen(t) == 1 )
        {
            nr=t[0]-'0';
            out<<REZ[nr]<<"\n";
        }
        else{

            nr=t[strlen(t)-2]-'0';
            nr*=10;
            nr+=t[strlen(t)-1]-'0';
            out<<REZ[nr]<<"\n";
        }
    }
    return 0;
}