JuliaCollections/DataStructures.jl

BinaryHeap constructor performs differently from heapify

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#639 opened on Jun 29, 2020

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Description

I noticed that BinaryHeap like BinaryMinHeap constructs a heap that just insert every element from an array to a empty heap. And the following x and y have the same order:

julia> nums = rand(1:20000, 2000);

julia> x = MutableBinaryMinHeap(nums);

julia> y = BinaryMinHeap(Int.([]));

julia> for i in nums 
           push!(y, i)
       end

However, there is an O(N) heap-building algorithm instead of O(NlogN), and function heapify is an implement. So why not use heapify instead of insert successively？

Sincerely.

Contributor guide

Research direction
Examine the BinaryHeap constructors and replace sequential insertion with a call to heapify for O(n) construction.
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julia
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backend
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