#include<stdio.h>
int putere(int n){
	int s=1,i;
	for(i=1;i<=n;i++)
		s=(s%10*n)%10;
	return s;
}
int main () {
	freopen("date.in","r",stdin);
	freopen("date.out","w",stdout);
	int i,n,v[30001],s=0,j;
	scanf("%d",&n);
	for(i=0;i<n;i++)
		scanf("%d",&v[i]);
	for(i=0;i<n;i++){
		s=0;
		for(j=1;j<=v[i];j++)
			s=(s+putere(j))%10;
			printf("%d\n",s);
		
	}
	return 0;
}