#include<stdio.h>
#include<string.h>
int x[20],l,u,m,i,n;
char nr[100];
int main()
{
	FILE *f,*g;
	x[0]=0;x[1]=1;x[2]=5;x[3]=2;x[4]=8;
	x[5]=3;x[6]=9;x[7]=2;x[8]=8;x[9]=9;
	x[10]=7;x[11]=8;x[12]=4;x[13]=7;x[14]=3;
	x[15]=8;x[16]=4;x[17]=1;x[18]=4;x[19]=4;
	f=fopen("cifra.in","r");
	g=fopen("cifra.out","w");
	fscanf(f,"%d",&n);
	for(i=1;i<=n;i++)
	{fscanf(f,"%s",&nr);
	l=strlen(nr);
	if(l==1){u=nr[l-1]-'0';fprintf(g,"%d\n",x[u]);}
	else{
		u=nr[l-1]-'0';
		m=(nr[l-2]-'0')/2;
		u+=10*((nr[l-2]-'0')%2);
		fprintf(g,"%d\n",(4*m+x[u])%10);}
	}
	fcloseall();
	return 0;
}