#include <stdio.h>
FILE *f=fopen("cifra.in","r"),*g=fopen("cifra.out","w");
int s,i,j,c,nr,sol[101];
char a,b,p;
int main(void)
{
	for (i=1;i<=100;i++)
	{
		j=i%4;
		c=i%10;
		if (j==0) j=4;
		while (j>1)
		{	c=(c*(i%10))%10; j--;}
		s=(s+c)%10;
		sol[i]=s;
	}
	int t;
	fscanf(f,"%d",&t);
	fscanf(f,"%c",&a);
	for (int k=1;k<=t;k++)
	{
	p='a';
	
	fscanf(f,"%c",&a);
	b=a;
	while (b>='0' && b<='9' && !feof(f))
	{
		fscanf(f,"%c",&b);
		if (b>='0' && b<='9' && !feof(f))
		{
			p=a;
			a=b;
		}
	}
	if (p>='0' && p<='9')
		nr=(p-'0')*10+a-'0';
	else nr=a-'0';
	s=0;
	fprintf(g,"%d\n",sol[nr]);
	}
	fclose(g);
	return 0;
}