var
  count : Integer;
  i : byte;
  number : uint64;
  N : Integer;
begin
  number := 1;
  Readln(count);
  for i:=1 to count do
  begin
    Readln(N);
    number := number * N;
  end;
      Assign(output, 'output.txt' ) ;
      Rewrite(output);
    Writeln(output, number);
end.