#include <fstream.h>
#include <math.h>
#include <string.h>

int ultima (int numar)
{
	long a=pow((numar%10), numar%4+4);
	return a%10;
}

int suma (int n)
{
	long S=0;
	for (int i=1; i<=n; i++)
	{
		S+=ultima (i);
	}
	return S%10;
}

int main ()
{
	 char string[100];
	 int j, a, T, b;
	 ifstream ins;
	 ins.open("cifra.in");
	 ins>>T;
	 ofstream ous;
	 ous.open("cifra.out");
	 for (j=0; j<T; j++)
	 {
		ins>>string;
		a=strlen(string);
		if (a==1)
		{
			ous<<suma (string[0]-'0')<<"\n";
		}
		else
		{
			b=((int)(string[a-1]-'0'))+10*((int)(string[a-2]-'0'));
			ous<<suma(b)%10<<"\n";
			/*else
			{
				ous<<((suma (9))*(string[1]-'0')+suma(string[0]-'0');
			}*/
		}

	 }
	 ins.close();
	 ous.close();
	 return 0;
}