All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info

Home > Logic
Mind-Swapping Machine (Posted on 2012-08-02) Difficulty: 3 of 5
I am a mad scientist, and I have invented a machine that will switch the minds of two people into each other's bodies.

Being mad, though, my machine has one fatal drawback: once two bodies have used the machine, then the machine will never work again on that particular pair of bodies (regardless of whose minds are inhabiting them currently).

Here's an example. Bodies A and B use the machine, so person a is in Body B, and person b is in Body A.

Body   A B C
person b a c

Next, suppose Bodies A and C switch, so person c is in Body A, and person b is in Body C.

Body   A B C
person c a b

Finally, B and C switch, so person a is in body C, and person b is back in Body B.

Body   A B C
person c b a

Unfortunately, bodies A and C have already gone through the machine, so the machine will not work on that pair again. Therefore, if we want to restore everyone to his original body, at least one more additional body is needed for temporary storage.

Question 1:
At the beginning, once bodies A and B switch, can they ever switch back, leaving all others in their rightful bodies when all is said and done? If so, how many total bodies would need to be involved (including A and B)?

Question 2:
Suppose n people continue to switch bodies with other members of their group (again, each pair of bodies can only use the machine once). How many total bodies, in terms of n, would need to be involved to sort everyone out?

No Solution Yet Submitted by Dustin    
Rating: 5.0000 (1 votes)

Comments: ( You must be logged in to post comments.)
  Subject Author Date
re: Part II clarificationDustin2012-08-03 04:04:21
QuestionPart II clarificationSteve Herman2012-08-02 12:31:43
Good news, everyone!Jyqm2012-08-02 12:30:09
SolutionAnswer to 1Math Man2012-08-02 10:40:58
Please log in:
Login:
Password:
Remember me:
Sign up! | Forgot password


Search:
Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (4)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2017 by Animus Pactum Consulting. All rights reserved. Privacy Information