#include<stdio.h>
int main()
{
long int t,n,ultc,c,x,i,j;
FILE *f,*g;
f=fopen("cifra.in","r");
g=fopen("cifra.out","w");
fscanf(f,"%ld\n",&t);
for(i=1;i<=t;i++)
	  {fscanf(f,"%ld\n",x);
		ultc=0;
      for(j=1;j<=x;j++)
              {c=j%10;
               ultc=(ultc+c*c)%10;}
      fprintf(g,"%ld\n",ultc);}
fclose(f);
fclose(g);
return 0;
}