#include<fstream>
using namespace std;
ifstream f("cifra.in");
ofstream g("cifra.out");
int t,x;
int ult1(int x)
{int p=1;
 for(int i=1;i<=x;i++)
  p*=(x%10);
 return p%10;
}
int ult2(int w)
{int i,s=0;
 for(i=1;i<=w;++i)
  s+=ult1(i);
 g<<s%10<<"\n";
}
int main()
{int i;
 f>>t;
 for(i=1;i<=t;++i)
 {f>>x;
  ult2(x);
 }
 return 0;
}