Frodo can meet either Sam, or Pippin, or Merry in the fog. One day
everyone came out to meet Frodo, but the fog was thick, and Frodo could
not see where everyone was, so he asked each of his friends to introduce
themselves.
The one who from Frodo’s perspective was on the left, said: "Merry is
next to me."
The one on Frodo’s right said: "The person who just spoke is
Pippin."
Finally, the one in the center announced, "On my left is Sam."
Identify who stood where, knowing that Sam always lies, Pippin sometimes
lies, and Merry never lies?