Cited By
View all- Nipkow TEberl MHaslbeck M(2020)Verified Textbook AlgorithmsAutomated Technology for Verification and Analysis10.1007/978-3-030-59152-6_2(25-53)Online publication date: 12-Oct-2020
Proof pearl: Braun trees
Pages 18 - 31
Abstract
Braun trees are functional data structures for implementing extensible arrays and priority queues (and sorting functions based on the latter) efficiently. Some well-known functions on Braun trees have not yet been verified, including especially Okasaki’s linear time conversion from lists to Braun trees. We supply the missing proofs and verify all of these algorithms in Isabelle, including non-obvious time complexity claims. In particular we provide the first linear-time conversion from Braun trees to lists. We also state and verify a new characterization of Braun trees as the trees t whose index set is the interval {1, …, size of t}.
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Index Terms
- Proof pearl: Braun trees
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Published: 22 January 2020
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- Stiftelsen för Strategisk Forskning
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View all- Nipkow TEberl MHaslbeck M(2020)Verified Textbook AlgorithmsAutomated Technology for Verification and Analysis10.1007/978-3-030-59152-6_2(25-53)Online publication date: 12-Oct-2020
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