const r:array[0..19] of byte=(
  0,1,5,2,8,3,9,2,8,7,7,8,4,7,3,8,4,1,5,4
);
var s:string;
    nr,err:byte;
    i,t:integer;
begin
  assign(input,'cifra.in'); reset(input);
  assign(output,'cifra.out'); rewrite(output);
  readln(t);
  for i:=1 to t do begin
    readln(s);
    if length(s)>2 then delete(s,1,length(s)-2);
    val(s,nr,err);
    writeln((4*(nr div 20)+r[nr mod 20])mod 10);
  end;
  close(input); close(output);
end.