#include <fstream>
//#include <cstring>

using namespace std;

ifstream f("cifra.in");
ofstream g("cifra.out");

int U[100];

int ucif(int n)
{
    int uc=n%10, r=n%4, p=1;
    if(r==0) r=4;
    while(r--)
        p*=uc;
    return p%10;
}

void precalcul()
{
    for(int i=1; i<100; i++)
        U[i]=(U[i-1]+ucif(i))%10;
}

int main()
{
    int T, ncif, rest;
    char sir[101];
    precalcul();
    f>>T;
    f.ignore();
    while(T--)
    {
        f.getline(sir, 101);
        //ncif=strlen(sir);
        ncif=f.gcount()-1;
        rest=sir[ncif-1]-'0';
        if(ncif>=2)
            rest+=(sir[ncif-2]-'0')*10;
        g<<U[rest]<<'\n';
    }
    f.close();
    g.close();
    return 0;
}