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A “graph” analog of this data structure can be used in distributed computing for data split between different nodes. For 10 points each:
[10h] Name this probabilistic data structure that consists of multiple linked lists. The first list contains all the elements in order, while each subsequent list contains a random subset of the previous one’s elements.
ANSWER: skip list [accept skip graph; prompt on list]
[10e] Operations on a skip list have this average-case big-O time complexity. This is also the average-case time complexity of binary search on a sorted array.
ANSWER: logarithmic [or O(log n); accept logarithms of any base, such as O(ln n) or O(log2n)]
[10m] Skip lists may be used to reduce these entities’ namesake contention in concurrent systems. Unlike semaphores, these synchronization primitives are always obtained and released by the same thread.
ANSWER: locks [or mutexes; accept lock contention or spinlocks]
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TournamentExact Match?HeardPPBEasy %Medium %Hard %
2025 ACF NationalsYes2015.0075%55%20%