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32 lines
747 B
Markdown
32 lines
747 B
Markdown
---
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title: "heaps-and-heapsort"
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aliases:
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tags:
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- cosc201
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---
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# 3 Heap Sort
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In place and ϴ(n lg n)
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- start with array
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- using itself as a heap, add the elements one at a time until all been added
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- Then remove them one at a time - the largest elements gets removed first and the place where is needs to be put gets freed from the map
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# 4 Heap sort vs Merge sort
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heap --> in place, ϴ(n lg n)
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merge --> not in place, Ο(n lg n)
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Merge is preferred because
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- MS can take advantage of partially sorted data (hence ϴ() vs Ο())
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- MS memory accesses are good fast
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- overwrites allow for optimizations that swaps do not
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extra memory cost of merge sort is negligible
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∴ Merge sort is faster
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