#include <stdio.h>
int main()
{
	long long int n, j, g, t, i, p ,c, u;

	freopen("cifra.in", "r", stdin);
	freopen("cifra.out", "w", stdout);

	scanf("%d\n", &t);

	for (i=1; i<=t; i++)
	{
		scanf("%lld\n", &n);

		for (j=1; j<=n; j++)
		{
			for (g=1; g<=n; g++)
			{
				c=j%10;
				p=c;
				c=c*p;
				c=c%10;
			}
			u=u+c;
			u=u%10;
		}
	printf("%d", u);
	}
	return 0;
}