#include<fstream.h>

int put(long n,int k)
{ int i;
long j=1;
for(i=1;i<=k;i++)
j=j*n;
return j%10;
}

int main()
{long n,s=0,q,l,t;
ifstream f("cifra.in");
ofstream g("cifra.out");
f>>l;
for(t=1;t<=l;t++)
{f>>n;
 s=0;
for(int i=1;i<=n;i++)
{q=i%10;

if(q==1||q==5||q==6) s+=q;
     else if(q==4){if(i%2==0)s+=6;
		 else s+=4;}
	 else if(q==9){if(i%2==0)s+=1;
		else s+=9;}
			else  {if(i%4==0){if(q==8||q==2)s+=6;
					   else if(q==7||q==3) s+=1;
					 }
				else s+=put(q,i%4);}


}
if(t==l) g<<s%10;
else  g<<s%10<<"\n";

}

g.close();
f.close();
return 0;
}