#include<iostream>
#include<fstream>
using namespace std;
int main ()
{
    int t,n,j,v[10]={0,1,4,9,6,5,6,9,4,1},s;
    ifstream x("cifra.in");
    ofstream y("cifra.out");
    x>>t;
    for(int i=1;i<=t;i++)
    {
    x>>n;
    s=0;
    for(j=1;j<=n;j++)
    {
        s+=v[j%10];
        if(j%5==0)
        s=s%10;
    }
    y<<(s%10);
    }
    x.close();
    y.close();
    return 0;
}