#include<stdio.h>
int i,t,j,x,s,p,cj;
FILE *f,*g;
int main ()
{
f=fopen("cifra.in","r");
fscanf(f,"%d",&t);
g=fopen("cifra.out","w");
for(i=1;i<=t;i++){s=0;
	fscanf(f,"%d",&x);
		for(j=1;j<=x;j++){p=j%10;cj=j%4;
				switch(p){
		case 0 :  break;

		case 1 : s=s+1;break;

		case 2 : switch(cj){
                case 0 : s=s+6;break;
                case 1 : s=s+2;break;
                case 2 : s=s+4;break;
                case 3 : s=s+8;break;}break;

		case 3 : switch(cj){
                case 0 : s=s+1;break;
                case 1 : s=s+3;break;
                case 2 : s=s+9;break;
                case 3 : s=s+7;break;}break;

		case 4 : switch(cj){
                case 0 : s=s+6;break;
                case 1 : s=s+4;break;}break;

		case 5 : s=s+5;break;
		case 6 : s=s+6;break;

		case 7 : switch(cj){
                case 0 : s=s+1;break;
                case 1 : s=s+7;break;
                case 2 : s=s+9;break;
                case 3 : s=s+3;break;}break;

		case 8 : switch(cj){
                case 0 : s=s+6;break;
                case 1 : s=s+8;break;
                case 2 : s=s+4;break;
                case 3 : s=s+2;break;}break;

		case 9 : switch(cj){
                case 0 : s=s+9;break;
                case 1 : s=s+1;break;}break;
		}}
	s=s%10;fprintf(g,"%d\n",s);
}
fclose(f);fclose(g);
return 0;
}