#include <iostream>
#include <fstream>
using namespace std;
ifstream f("cifra.in");
ofstream g("cifra.out");
int uc(int n,int k)
{
    if(n%10==0 || n%10==1 || n%10==5 || n%10==6) return n%10;
    if(n%10==4){
        if(k%2==0) return 6;
        else
            return 4;
    }
    if(n%10==2){
        switch(k%4){
        case 0:return 6;
        case 1:return 2;
        case 2:return 4;
        case 3:return 8;
        }

    }
    if(n%10==3)
        switch(k%4){
        case 0:return 1;
        case 1:return 3;
        case 2:return 9;
        case 3:return 7;
        }
    if(n%10==7)
        switch(k%4){
        case 0:return 1;
        case 1:return 7;
        case 2:return 9;
        case 3:return 3;
        }
    if(n%10==8)
        switch(k%5){
        case 0:return 6;
        case 1:return 8;
        case 2:return 4;
        case 3:return 2;
        }
    if(n%10==9){
        if(k%2==0) return 1;
        return 9;
    }

}

int sum(int n)
{
     int i;
     int s=0;
     for(i=1;i<=n;i++)
{
    s+=uc(i,i);

}
    return s%10;

}

int main()
{ int T,i;
   int N;
f>>T;
for(i=1;i<=T;i++)
{f>>N;g<<sum(N)<<'\n';}



    return 0;
}