2014-12-22 11:05:57 +01:00
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This directory contains a general purpose data structures, for use anywhere
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in the backend:
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binaryheap.c - a binary heap
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2015-01-23 21:06:29 +01:00
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hyperloglog.c - a streaming cardinality estimator
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2014-12-22 11:05:57 +01:00
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pairingheap.c - a pairing heap
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2014-12-22 16:52:08 +01:00
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rbtree.c - a red-black tree
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2014-12-22 11:05:57 +01:00
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ilist.c - single and double-linked lists.
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stringinfo.c - an extensible string type
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Aside from the inherent characteristics of the data structures, there are a
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few practical differences between the binary heap and the pairing heap. The
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binary heap is fully allocated at creation, and cannot be expanded beyond the
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allocated size. The pairing heap on the other hand has no inherent maximum
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size, but the caller needs to allocate each element being stored in the heap,
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while the binary heap works with plain Datums or pointers.
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The linked-lists in ilist.c can be embedded directly into other structs, as
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opposed to the List interface in nodes/pg_list.h.
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