#include <fstream>
#include <string.h>
using namespace std;
ifstream f("cifra.in");
ofstream g("cifra.out");
int i,j,n,p,val[101],numar,lng;
char sir[101];
int rec(int x, int y)
{
    if (!y)
        return 1;
    else if (y%2)
        return x%10*rec((x*x)%10, y/2)%10;
    else
        return rec((x*x)%10, y/2)%10;
}
int main()
{
    f>>n;
    for (i=1;i<=100;++i)
        val[i]=rec(i,i);
    for (i=1;i<=n;++i)
    {
        f>>sir;
        lng=strlen(sir)-1;
        numar=lng?(sir[lng-1]-'0')*10+(sir[lng]-'0'):sir[0]-'0';
        for (p=0,j=1;j<=numar;++j)
            p=(p+val[j])%10;
        g<<p<<"\n";
    }
}