#include<stdio.h>
int main()
{
long int t,n,ultc,c,x,i,j,v[30];
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",&v[i]);
		x=v[i];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;
}