#include<stdio.h>
#include<string.h>
int main(){
	FILE*in=fopen("cifra.in","r");
	FILE*out=fopen("cifra.out","w");
	int t,n,i,x,s,j,j1,aux,k,p;
	char nr[101];
	fscanf(in,"%d",&t);
	for(i=0;i<t;i++){
		fscanf(in,"%s",nr);
		n=strlen(nr);
		if(n==1)
			x=(nr[0]-'0');
		else
			x=(nr[n-2]-'0')*10+(nr[n-1]-'0');
		s=0;
		s=((x/20)*4)%10;
		for(j=1;j<=(x%20);j++){
			if(j%4==0)
				aux=4;
			else
				aux=j%4;
			j1=j%10;
			p=1;
			for(k=0;k<aux;k++)
				p=(p*j1)%10;
			s=(s+p)%10;
		}
		fprintf(out,"%d\n",s);
	}
	fclose(out);
	fclose(in);
	return 0;
}