#include <fstream>
using namespace std;
int main ()
{
    ifstream fin ("cifra.in");
    ofstream fout ("cifra.out");
    int n;
    fin>>n;
    int v[n];
    for (int i=0;i<n;++i)
    {
        int x,y,s=0;
        fin>>v[i];
        x=v[i]%10;
        y=(v[i]-x)/10;
        s=s+y*5;
        for (int i=1;i<=x;++i)
        {
            s=s+i*i;
        }
        fout<<s%10<<endl;
    }
}