#include<iostream>
#include<fstream>
using namespace std;
ifstream f("cifra.in");
ofstream g("cifra.out");
int main()
{ int i,n,x,c,uc,sc,t,j;
    f>>t;
    for(x=1;x<=t;x++)
	{ f>>n;
	sc=0;
    for(i=1;i<=n;++i)
    {
        c=i%10;
        uc=c;
        for (j=1;j<i;++j)
        uc=(uc*c)%10;
        sc+=uc;
    }
    sc%=10;
    g<<sc<<"\n";
	}
    return 0;

}