#include <fstream>
#include<string>
using namespace std;
int c[100];
int n,sum,i,a,b,j,t,k,p;
char s[10000];
int main()
{
	ifstream f("cifra.in");
	ofstream g("cifra.out");
	f>>t;
	for(k=1;k<=t;k++)
	{
		sum=0;
		n=k;
		a=0;
		for(i=1;i<=n;i++)
		{
			b=1;
			for(j=1;j<=i;j++)
				b=(b*i)%10;
			a=(a+b)%10;
		}
		c[k]=a;
	}
	for(k=1;k<=t;k++)
	{
		f>>s;
		n=strlen (s);
		if(n==1)
			g<<c[s[n-1]-'0']<<"\n";
		else
		{
			p=(s[n-2]-'0')*10+s[n-1]-'0';
			g<<c[p]<<"\n";
		}
	}
	
	return 0;
}