#include <iostream>
#include <fstream>
#include <math.h>
using namespace std;
ifstream f ("cifra.in");
ofstream g ("cifra.out");
int T,N,i,s,j,n;
int main()
{
    f>>T;
    for (i=1;i<=T;i++)
    {
        f>>N;
        s=0;
        for (j=1;j<=N;j++)
         {
             n=j;
             if (n>9) n=n%10;
             s=s+(int)pow(n,n)%10;
         }
        g<<s%10<<endl;
    }
    f.close();
    g.close();
    return 0;
}