#include <fstream>

using namespace std;

int main()
{
    ifstream f("cifra.in");
    ofstream g("cifra.out");
    int t,n,answer,c;
    //int a[10]={0,1,4,7,6,5,6,3,6,9};
    //int b[10]={0,1,6,3,6,5,6,7,4,9};
    int suma[10]={0,1,5,2,8,3,9,2,8,7};
    int sumb[10]={0,1,7,0,6,1,7,4,8,7};
    int cifra[4]={1,7,9,3};
    f>>t;
    for (int i=1; i<=t; i++)
    {
        f>>n;
        c=n/10;
        //g<<c<<" ";
        if (c>0)
            answer=cifra[c%10];
        else
            answer=0;
        if (c%2==0)
            answer+=suma[n%10];
        else
            answer+=sumb[n%10];
        g<<answer%10<<"\n";
    }
    return 0;
}