Lost in the lift

The familiar elevator from Cube Escape: Theatre, modified, however.

Now, let's suppose that we're stuck in a mysterious elevator, in which there're only two buttons, up and down. Each storey has a number to show how many storeys we'll go through if we push the button on this storey. So how do we move from our current storey to the hotel lobby (the 1st floor)?

Here's the perfect solution: