#include<fstream>
#include<iostream>
#include<stdlib.h>
using namespace std;
int i,j,x,k;
char n[100];
char t[100];
int c(int x)
{return x%10;}
int main()
{

ifstream f("in.txt");

ofstream g("out.txt");

f>>t;

int y=atoi(t);

for(i=1;i<=y;i++)

{f>>n;

x=atoi(n);

int s=0;

for(j=1;j<=x;j++)

{k=c(j);

switch(k)

{case 0: break;

case 1: s=s+1; break;

case 2:

if(j%4==1) s=s+2;

else if(j%4==2) s=s+4;

else if(j%4==3) s=s+8;

else s=s+6;

break;

case 3:

if(j%4==1) s=s+3;

else if(j%4==2) s=s+9;

else if(j%4==3) s=s+7;

else s=s+1;

break;

case 4:

if(j%2==1) s=s+4;

else s=s+6;

break;

case 5: s=s+5; break;

case 6:s=s+6; break;

case 7:

if(j%4==1) s=s+7;

else if(j%4==2) s=s+9;

else if(j%4==3) s=s+3;

else s=s+1;

break;

case 8:

if(j%4==1) s=s+8;

else if(j%4==2) s=s+4;

else if(j%4==3) s=s+2;

else s=s+6;

break;

case 9:

if(j%2==1) s=s+9;

else s=s+1;}

s=s%10;}
g<<s<<endl;}}