Parallel detection of all palindromes in a string. (English) Zbl 0873.68039

Summary: This paper presents two efficient concurrent-read concurrent-write parallel algorithms that find all palindromes in a given string: 1. An \(O(\log n)\) time, \(n\)-processor algorithm over general alphabets. In the case of constant size alphabets the algorithm requires only \(n/\log n\) processors, and thus achieves an optimal-speedup. 2. An \(O(\log\log n)\) time, \(n\log n/\log\log n\)-processor algorithm over general alphabets. This is the fastest possible time with the number of processors used. These new results improve on the known parallel palindrome detection algorithms by using smaller auxiliary space and either by making fewer operations or by achieving a faster running time.


68P10 Searching and sorting


Full Text: DOI


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