A one-kilometer long corridor has two exits, both of which are big fireplaces.

Some skeletons located in this corridor walk at a speed of one meter per second. Once a skeleton reaches one of the exits, he is instantaneously consumed. If two skeletons hit one eachother, they bounce and walk immediately in the opposite direction.


Q1: Can the skeletons stay in the corridor for an infinite time?

Q2: Knowing that two skeletons cannot be in the same initial position, how can one place 64 skeletons (position, direction) in a way such that the last skeleton stays in the corridor as long as possible?

(Thanks to T.K.)