var f1,f2:text;
    t,j,x,u,r,c,c1,c2:longint;
    s:string;
    k:integer;
function xlax(x:integer):integer;
var r,u,ult,i:longint;
begin
  r:=x mod 4;
  if r=0 then r:=4;
  u:=1;
  ult:=x mod 10;
  for i:=1 to r do
    u:=u*ult mod 10;
  xlax:=u;
end;

function suma(n:integer):integer;
var u,i:longint;
begin
  u:=0;
  for i:=1 to n do
    u:=(u+xlax(i))mod 10;
  suma:=u;
end;


begin
  assign(f1,'cifra.in');
  reset(f1);
  assign(f2,'cifra.out');
  rewrite(f2);
  readln(f1,t);
  for j:=1 to t do
  begin
  readln(f1,s);
  val(s[length(s)],c1,k);
  val(s[length(s)-1],c2,k) ;

  if length(s)>=2 then
    x:=c2*10+ c1
  else x:=c1;
  c:=x div 20;
  r:=x mod 20;
  u:=c*4 mod 10;
  u:=(u+suma(r))mod 10;
  writeln(f2,u);
  end;
  close(f1);
  close(f2);
end.