#include <iostream>
#include <fstream>
using namespace std;

ifstream f("cifra.in");
ofstream g("cifra.out");
int S;
long N,i,j,a;
int main()
{ f>>N;
  for (j=1;j<=N;j++) { f>>a; S=0;
    for (i=1;i<=a;i++)
{   if (i%10==1) S=S+1;
    if (i%10==2) {if (i%4==1) S=S+2;
                  if (i%4==2) S=S+4;
                  if (i%4==3) S=S+8;
                  if (i%4==0) S=S+6;}
    if (i%10==3) { if (i%4==1) S=S+3;
                   if (i%4==2) S=S+9;
                   if (i%4==3) S=S+7;
                   if (i%4==0) S=S+1;}
    if (i%10==4) { if (i%2==1) S=S+4;
                    else S=S+6;}
    if (i%10==5) S=S+5;
    if (i%10==6) S=S+6;
    if (i%10==7) {if (i%4==1) S=S+7;
                  if (i%4==2) S=S+9;
                  if (i%4==3) S=S+3;
                  if (i%4==0) S=S+1;}
    if (i%10==8) {if (i%4==1) S=S+8;
                  if (i%4==2) S=S+4;
                  if (i%4==3) S=S+2;
                  if (i%4==0) S=S+6;
                 }
   if (i%10==8) { if (i%2==1) S=S+9;
                  else S=S+1;}}
g<<S%10<<"\n";}
    return 0;
}