#include<stdio.h>
#include<string.h>
/*
int main()
{
	FILE *in=fopen("cifra.in","r"), *out=fopen("cifra.out","w");
	int i,j,s=0,c;
	for(i=1;i<=20;++i)
	{
		c=i;
		for(j=1;j<i;++j)
			c=(c*i)%10;
		s+=c;
		fprintf(out,"%d,",c);
	}
	fprintf(out,"\n%d\n",s);
	s=0;
	for(i=21;i<=40;++i)
	{
		c=i;
		for(j=1;j<i;++j)
			c=(c*i)%10;
		fprintf(out,"%d ",c);
		s+=c;
	}
	fprintf(out,"\n%d\n",s);
	return 0;
}
*/

int main()
{
	FILE *in=fopen("cifra.in","r"), *out=fopen("cifra.out","w");
	char n[101];
	int t,q,j,x,c,i,v[20]={1,4,7,6,5,6,3,6,9,0,1,6,3,6,5,6,7,4,9,0};
	fscanf(in,"%d",&t);
	for(j=0;j<t;++j)
	{
		fscanf(in,"%s",&n);
		q=strlen(n);
		if(q>1)
			x=(n[q-2]-'0')*10+n[q-1]-'0';
		else
			x=n[0]-'0';
		c=((x/20)*4)%10;
		for(i=0;i<x%20;++i)
			c=(c+v[i])%10;
		fprintf(out,"%d\n",c);
	}
	fclose(in);
	fclose(out);
	return 0;
}