#include<stdio.h>
#include<string.h>
int main()
{
	freopen("cifra.in","r",stdin);
	freopen("cifra.out","w",stdout);
	int t,x,n,i,s=0,c,d,k;
	char sir[101];
	scanf("%d",&t);
	while(t){
		scanf("%s",sir);
		n=strlen(sir);
		if(n==1)
			x=sir[0]-'0'+0;
		else
			x=10*(sir[n-2]-'0')+sir[n-1]-'0';
		for (i=1;i<=x;i++){
            c=i%4;
			if (c==0)c=4;
			d=1;
            for (k=1;k<=c;k++){
                d=d*(i%10)%10;
            }
            s=(s+d)%10;
		}
		printf("%d\n",s);
		t--;
	}
}