From: Li Chen <chen_li3@...>
Date: 2009-02-12T01:34:30+09:00
Subject: Re: how to do the recursion

Matthew Williams wrote:
>> The main idea behind recursion is that we break a problem into a
> representation of the same problem.  In this case, we are taking a
> number, n.  We want the value of that n, modulo 2, + the binary value of
> (n / 2).
> 
> Using that approach, for 4, we'd get:
> 
> (n%2) + ((n/2)%2) + ((n/2)/2)%2
> 
> which is "001" -- the reverse of what we were wanting.  However, if we
> turn it around, we can say that the binary representation of n is
> equivalent to:
> 
> the binary representation of (n/2) + (n modulo 2)

Hi Matt,

Thank you very much. Your explanation is so sweet!



Li
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