Edward M. McCreight

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Organization and maintenance of an index for a dynamic random access file is considered. It is assumed that the index must be kept on some pseudo random access backup store like a disc or a drum. The index organization described allows retrieval, insertion, and deletion of keys in time proportional to logk I where I is the size of the index and k is a(More)
We present a new data structure for maintaining a set of records in a linear list according to their key values. This data structure has the property that we can keep a number of <italic>fingers</italic> at points of interest in the key space (e.g., the beginning or the end of the list), so that access and modification in the neighborhood of a finger is(More)
The structure of the functions computable in time or space bounded by t is investigated for recursive functions t. The t-computable classes are shown to be closed under increasing recursively enumerable unions; as a corollary the primitive recursive functions are shown to equal the t-computable functions for a certain recursive t. Any countable partial(More)
A strategy is presented for pagination of B<supscrpt>*</supscrpt>-trees with variable-length records. If records of each length are uniformly distributed within the file, and if a wide distribution of record lengths exists within the file, then this strategy results in shallow trees with fast access times. The performance of this strategy in an application(More)
This paper presents a method for circular range searching in 2D geographical data for GIS. The proposed is based on the priority search tree (PST) developed by Edvard T. McCreight in the mid eighties. The Priority Search Tree is a data structure used for performing semi-infinite range queries. In the solution presented in this paper, the two operation of(More)
Partial recursive functions which equal the amount of time or space required by computations have special properties which distinguish them from arbitrary partial recursive functions. Our main result illustrates a property of running times similar in interpretation to Borodin's gap theorem. The proof is based on the construction of difficult to compute(More)