var fin, fout:text;
    ti, t:integer; n, i, j, sum, p:byte;
    s:string;
begin
  assign(fin, 'cifra.in');
  reset(fin);
  assign(fout, 'cifra.out');
  rewrite(fout);
  readln(fin, t);
  for  ti:=1 to t do
  begin
    readln(fin, s);
    n:= ord(s[length(s)])-ord('0');
    if length(s)>1 then n:=n+ (ord(s[length(s)-1])-ord('0'))*10;
    sum:=0;
    for i:=1 to n do
    begin
       p:=1;
       for j:=1 to i mod 100 do
         p:= (p * i) mod 10;
       sum:= (sum + p) mod 10;
    end;
    writeln(fout, sum mod 10);
  end;
  close(fin);
  close(fout);
end.