#include <iostream>
#include <fstream>
#include <cmath>
using namespace std;
ifstream in("cifra.in");
ofstream out("cifra.out");
int main()
{
int n,baza,exp,s,uc,i,k,T;
in>>T;
for(k=1;k<=T;k++)
{
s=0;
in>>n;
for(i=1;i<=n;i++)
{
if(i%10==0) uc=0;
if(i%10==1) uc=1;
if(i%10==5) uc=5;
if(i%10==6) uc=6;
if(i%10==9) uc=9;
else
{
baza=i%10;
if(i%4) exp=i%4;
else exp=4;
uc=pow((float)baza,exp);
}
s=s+uc%10;
}
out<<s%10<<"\n";
}
return 0;
}