#include <iostream>
#include <fstream>
#include <string.h>
using namespace std;
ifstream f("cifra.in");
ofstream g("cifra.out");
int v[10][4]={0,0,0,0,1,1,1,1,6,2,4,8,1,3,9,7,6,4,6,4,5,5,5,5,6,6,6,6,1,7,9,3,6,8,4,2,1,9,1,9};
int citire()
{
    int T,x,ci,p,S,j,k;
    char c[100];
    f>>T;
    for(int i=0;i<T;++i)
    {
        f>>c; x=0;
        for(k=1;k<=strlen(c);++k)
        {
            x*=10;
            x+=(c[strlen(c)-k]-'0');
        }
        S=0;
        for(j=1;j<=x;++j)
        {
            ci=j%10;
            p=j%4;
            S+=v[ci][p];
        }
        g<<S%10<<"\n";
    }
}
int main()
{

    citire();
    return 0;
}