#include<fstream.h>
#include<string.h>
int main ()
{
	ifstream fcin("cifra.in");
	FILE *f=fopen("cifra.in","r");
	ofstream fcout("cifra.out");
	char*s1;s1=new char[102];
	int i,j,n,uc,x,z,s=0,t,a,c[21]={0,1,4,7,6,5,6,3,6,9,0,1,6,3,6,5,6,7,4,9,0};
	char y;
	fcin>>s1;
	t=atoi(s1);
	uc=4;
	for(i=1;i<=t;i++)
		{uc=4;s=0;
		 fcin>>s1;
		 n=strlen(s1);
		 if(n>1)strcpy(s1,s1+n-2);
		 x=atoi(s1);
		 uc=(uc*((x/10)/2))%10;
		 for(j=1;j<=x%20;j++)
			 s=s+c[j];
		 uc=(uc+s)%10;
		 fcout<<uc<<'\n';}
		return 0;
}