#include <fstream>
using namespace std;
ifstream f("cifra.in");
ofstream g("cifra.out");

int U[100];///U[i]=Uc(1^1+2^2+...+i^i)

int ucif(int n) ///ult cifra a lui n^n
{
    int uc=n%10,
        r=n%4,
        p=1;
    if (r==0) r=4;
    while(r--)
        p*=uc;
    return p%10;
}

int main()
{
    int T,ncif,rest;
    char sir[101];
    for(int i=1;i<100;i++)
        U[i]=(U[i-1]+ucif(i))%10;
    f>>T;
    f.get();
    while(T--)
    {
        f.getline(sir,101);
        ncif=f.gcount()-1;
        rest=sir[ncif-1]-'0';
        if (ncif>=2)
            rest+=(sir[ncif-2]-'0')*10;
        g<<U[rest]<<'\n';
    }
    return 0;
}