A Catalogue of Algorithms for Building Weak Heaps

An array-based weak heap is an efficient data structure for realizing an elementary priority queue. In this paper we focus on the construction of a weak heap. Starting from a straightforward algorithm, we end up with a catalogue of algorithms that optimize the standard algorithm in different ways. As the optimization criteria, we consider how to reduce the number of instructions, branch mispredictions, cache misses, and element moves. We also consider other approaches for building a weak heap: one based on repeated insertions and another relying on a non-standard memory layout. For most of the algorithms considered, we also study their effectiveness in practice.