knuth-morris-pratt – Tarik Billa

Why does String.indexOf() not use KMP?

December 4, 2023 by Tarik

KMP has better worst-case performance, but actually requires a little bit of up-front computation (to generate the table of offsets). It also requires an initial memory allocation, which could also impact performance. For (presumably) common use-cases of searching in relatively short strings, this might actually end up slower than the primitive implementation. This, bundled with … Read more

When to use Rabin-Karp or KMP algorithms?

August 10, 2023 by Tarik

When you want to search for multiple patterns, typically the correct choice is to use Aho-Corasick, which is somewhat a generalization of KMP. Now in your case you are only searching for 3 patterns so it may be the case that KMP is not that much slower(at most three times), but this is the general … Read more