#include <fstream.h>
typedef unsigned long int longplus;



int a[10][5] ={{0,0,0,0,0},
	       {1,1,1,1,1},
	       {6,2,4,8,6},
	       {1,3,9,7,1},
	       {6,4,6,4,6},
	       {5,5,5,5,5},
	       {6,6,6,6,6},
	       {1,7,9,3,1},
	       {6,8,4,2,6},
	       {1,9,1,9,1}};

int rezolva(longplus n){
  longplus i,sum;
  sum=0;
  for (i=1;i<=n;i++){
    sum+=a[i%10][i%4];
    sum%=10;
  }
  return sum;
}


int main(){
  longplus x,t;
  ifstream f("cifra.in");
  ofstream g("cifra.out");
  f>>t;
  for (int i=1;i<=t;i++){
    f>>x;
    g<<rezolva(x)<<"\n";
  }
  f.close();
  g.close();

  return 0;
}