Can i use Pentax or Olympus lens on Nikon?

Do they auto focus on Nikon d5100? ( 50mm and 135 mm one)

No, don't expect the auto focus to work even if you do use an adapter ring.

Even if you can find a lens adapter, they will not autofocus or auto expose - you will have to manually do both. Most find this a real pain. And if that is not enough, the image quality is often not acceptable - at least from what you would expect from a DSLR.

Both Pentax (especially SMC Takumars!) and Olympus made some fine lenses but their registration distance (ie the distance between the back of the lense and the film/sensor) is very different so that, even if an adaptor is available one is unlikely to be able to focus to infinity. There are optical adaptors but these reduce the image quality and that rather defeats the object. Only lenses made specifically for that make of camera will autofocus. There are no adaptors that maintain that function.

The Nikon F mount is narrower than most. I don't think many lenses with other mounts can be adapted to fit on a Nikon body. The old 42mm screw thread lenses can. Disadvantages of trying to do that is as others have noted.

No today's digital DSLR's are manufactor specific. That means you can only use Nikon (digital) lenses and some manufacturers that make digital lenses for the Nikon mount, such as Tamron and Sigma.

Pentax has the only lens mount that allows lenses sold for film cameras to be used on today's digital cameras. I just purchased a used Pentax 100mm macro lens for my current Pentax DSLR camera for $500 less than the new lens Pentax offers!

The main reason for this is that the stabilization feature is built into the Pentax camera body not each lens like Canon & Nikon do!