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Re: Is there a shorter solution ?

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On 08/10/2011 02:26 PM, HumbleWorker wrote:
> On Aug 10, 9:43 pm, tom st denis <t...@iahu.ca> wrote:
...
>> int numA;
>> int main()
>> {
>>    char *k = "abababababawhatever";
>>    while(*k) numA += *k++ == 'a';
>>    printf("Number of a's = %d\n", numA);
>>    return 0;
>>
>> }
>>
>> :-)
> 
> I am curious about one more thing. What would be the considerations of
> efficiency when we use a for loop like this instead of the while loop
> above ?
> 
> int main()
> {
> 	int numA = 0;
> 	char* k = "abababababawhatever";
> 	for (; *k; numA += *k++ == 'a');
> 	printf("Number of a's = %d\n", numA);
> 	return 0;
> }

The while-for conversion has no efficiency implications. Those parts of
the two programs are precisely equivalent, and if you're using a
compiler that isn't smart enough to recognize that fact and optimize
them the same way, you've got much bigger problems than simple
optimization to worry about.

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Is there a shorter solution ? HumbleWorker <amardeep.developer@gmail.com> - 2011-08-06 10:25 -0700
  Re: Is there a shorter solution ? Ike Naar <ike@sdf.lonestar.org> - 2011-08-06 17:42 +0000
  Re: Is there a shorter solution ? John Gordon <gordon@panix.com> - 2011-08-06 17:44 +0000
    Re: Is there a shorter solution ? Kenneth Brody <kenbrody@spamcop.net> - 2011-08-08 09:47 -0400
      Re: Is there a shorter solution ? Keith Thompson <kst-u@mib.org> - 2011-08-08 08:09 -0700
        Re: Is there a shorter solution ? HumbleWorker <amardeep.developer@gmail.com> - 2011-08-10 07:20 -0700
  Re: Is there a shorter solution ? tom st denis <tom@iahu.ca> - 2011-08-10 09:43 -0700
    Re: Is there a shorter solution ? HumbleWorker <amardeep.developer@gmail.com> - 2011-08-10 09:51 -0700
      Re: Is there a shorter solution ? James Kuyper <jameskuyper@verizon.net> - 2011-08-10 12:57 -0400
        Re: Is there a shorter solution ? HumbleWorker <amardeep.developer@gmail.com> - 2011-08-10 10:13 -0700
          Re: Is there a shorter solution ? blp@cs.stanford.edu (Ben Pfaff) - 2011-08-10 10:17 -0700
            Re: Is there a shorter solution ? HumbleWorker <amardeep.developer@gmail.com> - 2011-08-10 10:29 -0700
              Re: Is there a shorter solution ? tom st denis <tom@iahu.ca> - 2011-08-10 11:29 -0700
                Re: Is there a shorter solution ? "J. J. Farrell" <jjf@bcs.org.uk> - 2011-08-11 03:02 +0100
            Re: Is there a shorter solution ? Kenneth Brody <kenbrody@spamcop.net> - 2011-08-12 11:39 -0400
              Re: Is there a shorter solution ? Keith Thompson <kst-u@mib.org> - 2011-08-12 09:06 -0700
          Re: Is there a shorter solution ? James Kuyper <jameskuyper@verizon.net> - 2011-08-10 14:00 -0400
          Re: Is there a shorter solution ? Seebs <usenet-nospam@seebs.net> - 2011-08-11 01:46 +0000
        Re: Is there a shorter solution ? Keith Thompson <kst-u@mib.org> - 2011-08-10 11:49 -0700
          Re: Is there a shorter solution ? James Kuyper <jameskuyper@verizon.net> - 2011-08-10 15:03 -0400
            Re: Is there a shorter solution ? Keith Thompson <kst-u@mib.org> - 2011-08-10 13:23 -0700
      Re: Is there a shorter solution ? gordonb.d3r7p@burditt.org (Gordon Burditt) - 2011-08-10 18:15 -0500
    Re: Is there a shorter solution ? HumbleWorker <amardeep.developer@gmail.com> - 2011-08-10 11:26 -0700
      Re: Is there a shorter solution ? James Kuyper <jameskuyper@verizon.net> - 2011-08-10 15:14 -0400

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