#include<stdio.h>
int prod,n,k,i,j,v[1000],sum;
int main()
{
	freopen("cifra.in","r",stdin);
	freopen("cifra.out","w",stdout);
	scanf("%d",&n);
	for(i=1;i<=n;++i)
	{
		scanf("%d",&v[i]);
		prod=1;
		sum=0;
		for(j=1;j<=v[i];j++)
		{
			prod=1;
			for(k=1;k<=j;k++)
				prod=prod*j%10;
			sum=(sum+prod)%10;
		}
		printf("%d\n",sum);
	}
	return 0;
}