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Star Trek

Someone posted this on a message board - My answer is below, can anyone see a better way to do it ?

Aliens capture Captain Kirk and 50 of his crew. The aliens tell them that they must pass a test to survive. The aliens will keep each human in solitary confinement and every day will select one human at random to
bring into the "star chamber". In the star chamber there is an orb that changes from green to yellow to red and back to green when touched. The visiting human can touch the orb to change it to any color or leave it
alone before the aliens put him back in confinement. The aliens will not change the state of the orb. The orb starts out in the green state. While in confinement the humans will not be able to see the orb, know who has been selected that day or communicate with each other. During any visit to the star chamber a human may state that all the captured humans have visited the star chamber. If this statement is true then all the crew will be freed. If it is false they will all be turned into tribbles (this is an undesirable result). What strategy should the humans decide upon before they are put into solitary confinement?


Answer:
Captain Kirk is the counter.
Rules for the others. If it is green put it to yellow if you havent touched it. If it is yellow put it to red if you havent touched it yet. If you have touched it dont touch it again. If its red and you haven't touched it dont touch it yet.
Every time Kirk enters he will know that either one or two more people have been in the room and he adds these to his count, and sets the orb back to green. When he reaches 50 he will know that everyone has been in the room and he can announce it.

Nicholas Harvey
Friday, October 11, 2002

this is a downgraded version of another puzzle
which already appeared on this site, but was
shamelessly ripped off of ibm´s ponder this page..

this version is just crappier, dont know why someone
came up with it..

Cheradenine Zakalwe
Monday, October 21, 2002

Much more interesting question (but not one I would want to ask or answer at an interview)

How long on average would it take the Captain to free his crew?

David Clayworth
Wednesday, November 20, 2002

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