Hi!
Here are some statistics:
- average haystack length: 624.2
- average needle length: 1.9 ! -> 63% of needles of length 1
- avg length of haystacks shorter than avg: 41.0 -> 85% of all haystacks
- avg length of haystacks longer than avg: 5685.11
I think it would be interesting to see same excluding 1-char needles
since in this case it should do one-char lookup (btw, if we don't do it
on C level, it might be a good idea to).
Although strpos implements fix for that, some other functions don't. My idea
is than to implement ZEND_MEMNSTR once again in shape:
if (needle_len = 1)
here just linear sweep
else if haystack_len < 5000 (5000 is arbitrary - maybe some more tests
needed to choose good value)
original implementation (as it is the best one in this case)
else
BM/KMP (i think BM will be better in this case, as some people
suggested)
I'm not sure very big haystacks really worth the trouble - how many of
them are used? It may be interesting to see medians instead of averages
for that. But len=1 I think worth having special case.
--
Stanislav Malyshev, Zend Software Architect
[EMAIL PROTECTED] http://www.zend.com/
(408)253-8829 MSN: [EMAIL PROTECTED]
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