_keydown(key number) will tell whether a particular key code is being pressed the moment you call it
So upArrow = _keydown(18432) ' IDE menu Tools > Insert Keycode gets 18432 when press up arrow
leftArrow = _keydown(19200)
So upArrow = _keydown(18432) ' IDE menu Tools > Insert Keycode gets 18432 when press up arrow
leftArrow = _keydown(19200)
b = b + ...