Interview question: f(f(n)) == -n

Posted by Hrvoje Prgeša on Stack Overflow See other posts from Stack Overflow or by Hrvoje Prgeša
Published on 2009-04-08T21:04:18Z Indexed on 2010/03/18 23:11 UTC
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job-interview

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integers

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A question I got on my last interview:

Design a function f, such that:
f(f(n)) == -n
Where n is a 32 bit signed integer; you can't use complex numbers arithmetic.

If you can't design such a function for the whole range of numbers, design it for the largest range possible.

Any ideas?

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