Resilient Quicksort and Selection
نویسندگان
چکیده
We consider the problem of sorting a sequence of n keys in a RAM-like environment where memory faults are possible. An algorithm is said to be δ-resilient if it can tolerate up to δ memory faults during its execution. A resilient sorting algorithm must produce a sequence where every pair of uncorrupted keys is ordered correctly. Finocchi, Grandoni, and Italiano devised a δ-resilient deterministic mergesort algorithm that runs in O(n log n + δ) time. We present a δ-resilient randomized algorithm (based on quicksort) that runs in O(n log n + δ √ n log n) expected time and its deterministic variation that runs in O(n log n + δ √ n log n) worst-case time. This improves the previous known result
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