#include <fstream>
#include <iostream>
#include <iomanip.h>
#include <string.h>

using namespace std;
fstream fin("cifra.in",ios::in),fout("cifra.out",ios::out);
int r[21]={0,1,5,2,8,3,9,2,8,7,7,8,4,7,3,8,4,1,5,4,4},v;
char N[200];
int t,i,l;
int main(){
    fin>>t;
    for (i=1;i<=t;i++){
      fin>>N; l=strlen(N);
      if (l=1) v=N[0]-48;
      else {
        v=N[l-2]*10+N[l-1]-528;    
      }         
      fout<<(4*(v/20)+r[v%20])%10<<endl;
    }        
   fin.close(); fout.close();
}