Hi,
I'm looking for the algorithm which does the lowest number of
comparison for the string matching problem (in the worst case).
I know that the complexity is liniar in the length of the strings, but
I'm interested in finding the actual number of comparisons.
The lowest number (theoretical) is m-n+1, but as far as I know no
algorithm has achived this limit.
(where m is the lenght of the text and n is the length of the pattern).
Thanks,
Laura
2  2715 
laura wrote:
>
I'm looking for the algorithm which does the lowest number of
comparison for the string matching problem (in the worst case).
I know that the complexity is liniar in the length of the strings,
but I'm interested in finding the actual number of comparisons.
The lowest number (theoretical) is m-n+1, but as far as I know no
algorithm has achived this limit.
(where m is the lenght of the text and n is the length of the
pattern).
This is off-topic here. Try comp.programmin g. Cross posted and
followups set.
Search for Boyer-Moore and Knuth-Morris-Pratt algorithms.
Sedgewicks "Algorithms " covers it nicely. KMP is nice in that it
avoids backtracking and works with streams.
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In article <11************ **********@e3g2 000cwe.googlegr oups.com>,
laura <la************ *@gmail.comwrot e:
>I'm looking for the algorithm which does the lowest number of
comparison for the string matching problem (in the worst case).
That's an algorithms question, not a C specific question, so you
are advised to check with a newsgroup that deals with algorithms.
>I know that the complexity is liniar in the length of the strings, but
I'm interested in finding the actual number of comparisons.
You haven't defined *which* "string matching problem" you are
dealing with. It is also rather odd that you are concentrating
on the worst case to the exclusion of the average case.
>The lowest number (theoretical) is m-n+1, but as far as I know no
algorithm has achived this limit.
That's not the theoretical limit when you take into account locale
problems and case sensitivity...
--
"law -- it's a commodity"
-- Andrew Ryan (The Globe and Mail, 2005/11/26) This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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