#include<stdio.h>
int main()
{long unsigned t,c,i, n,j,s;
FILE *f,*g;
f=fopen("cifra.in","r");
g=fopen("cifra.out","w");
fscanf(f,"%ld",&t);
for (i=1; i<=t; i++)
	{fscanf(f,"%ld",&n);
	s=0;
	for (j=1; j<=n; j++)
		{c=(int)j%10;
		switch(c)
		{case 0:s=s+c; break;
		case 1: s=s+c;break;
		case 2: switch ( j%2)
						{case 0: s=s+4; break;
						case 1: s=s+8; break;
						case 2:s=s+6;break;
						case 3:s=s+2; break;  }; break;
		case 3: switch ( j%3)
						{case 0:s=s+7; break;
						case 1: s=s+1; break;
						case 2: s=s+3; break;
						case 3: s=s+9; break;} break;
		case 4: switch (j%4)
						{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(j%7)
			{case 0: s=s+9; break;
			case 1: s=s+3;      break;
			case 2: s=s+1;break;
			case 3 : s=s+7; break;};break;
		case 8: switch (j%8)
				{case 0: s=s+4; break;
				case 1: s=s+2; break;
				case 2:s=s+6; break;
				case 3:s=s+8; break;};break ;
		case 9: switch(j%9)
				{case 0: s=s+1;    break;
				case 1: s=s+9;break;     }break;}}
		fprintf (g,"%d\n",s%10);}
fclose(f);
fclose(g);
return 0;}