#include<fstream.h>
#include<iostream.h>
#define IN ifstream fin("cifra.in");
#define INC fin.close();
#define OUT	ofstream fout("cifra.out");
#define OUTC fout.close();
int main(){
int n,c,last,prod;
IN OUT fin>>n;for(;n;--n){
fin>>c;
last=0;
for(int i=1;i<=c;i++){
prod=1;
for(int j=1;j<=i;j++){
	prod=(prod*(i%10))%10;}
last=(last+prod)%10;}
fout<<last<<'\n';}
INC OUTC
return 0;}