#include <fstream>

using namespace std;
int i,p,j,a[101],t,x,ucif,pen;
string s;
ifstream f("cifra.in");
ofstream g("cifra.out");
int main()
{
    for (i=1;i<=100;i++)
    {
        p=1;
    for (j=1;j<=i;j++)
    p=p*i%10;
    a[i]=(a[i-1]+p)%10;
    }
    f>>t;
    for (i=1;i<=t;i++)
    {
        f>>s;
        x=s.length();
        ucif=s[x-1]-'0',pen=s[x-2]-'0';
        if (x==1) g<<a[ucif]<<'\n';
        else g<<a[pen*10+ucif]<<'\n';
    }
    return 0;
}