#include<stdio.h>
int suma (int n)
{
int i,s,k;
    s=0;
    for (i=1;i<=n;i++)
       {
       k=i%10;
       if (k==0||k==1||k==5||k==6||k==9)
	   {
	   s+=k;
	   s=s%10;
	   }
       else
	  if (k==2)
	     {
	     if (i%4==0)
	       {
	       s+=6;
	       s=s%10;
	       }
	     else
		{
		s+=4;
		s=s%10;
		}
	     }
       else
	  if (k==3)
	  {
	     if (i%4==1)
	       {
	       s+=3;
	       s=s%10;
	       }
	     else
		{
		s+=7;
		s=s%10;
		}
	     }
	  else
	 if (k==7)
	   {
	     if (i%4==1)
	       {
	       s+=7;
	       s=s%10;
	       }
	     else
		{
		s+=3;
		s=s%10;
		}
	     }
	 else
	   if (k==4)
	      {
	      s+=6;
	      s=s%10;
	      }
	 else
	   if (k==8)
	      {
	     if (i%4==0)
	       {
	       s+=6;
	       s=s%10;
	       }
	     else
		{
		s+=4;
		s=s%10;
		}
	     }
       }
return s;
}
int main()
{
int n, i,x,s;
FILE *f=fopen("cifra.in","r");
fscanf(f,"%d",&n);
FILE *g=fopen("cifra.out","w");
for (i=0;i<n;i++)
    {
    fscanf(f,"%d",&x);
    s=suma(x);
    fprintf(g,"%d",s);
    fprintf(g,"\n");
    }
fclose(f);
fclose(g);
return 0;
}