#include <iostream>
#include <fstream>
#include <cmath>
#include <cstring>
using namespace  std;

ifstream fin("cifra.in");
ofstream fout("cifra.out");

const int T=20;

int uc_s[T];
char v[101];

int main() {
   for (int i=1;i<T;i++) {
      int cif=i%10;
      int exp=i%4;
      if (exp==0) {
         exp=4;
      }
      int putere=1;
      for (int j=0;j<exp;j++) {
         putere*=cif;
      }
      putere%=10;
      uc_s[i]=(uc_s[i-1]+putere)%10;
   }

   int t;
   fin>>t;
   for (int i=0;i<t;i++) {
      fin>>v;
      int nr_cif=strlen(v);
      int n=v[nr_cif-1]-'0';
      if (nr_cif>1) {
         n+=(v[nr_cif-2]-'0')*10;
      }
      int nr_grupe_20=n/20;
      int rest_grupe=n%20;
      fout<<(nr_grupe_20*4+uc_s[rest_grupe])%10<<'\n';
   }


}