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DualPivotQuicksort problem #3

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adem0x opened this issue Mar 18, 2016 · 0 comments

adem0x commented Mar 18, 2016

I am not going to claim to understand DPQS (DualPivotQuicksort) algorihm nor the implementation.

All I did was to convert the generic parts to straight forward Cardinal types --so that I could use it in older versions of Delphi.

And, before comparing speeds with the usual QuickSort, I thought I might just test whether DPQS does actually sort things the way it is supposed to.

So, I checked it against QuickSort, BubbleSort and --as well as-- a known-to-be-good presorted array; and it seems DPQS has a problem.

Now.. I am pretty sure I haven't made any typos during generic-to-realtype conversion.

I have enclosed a very small project (just sources); could you please look at it and see what's wrong.

QuickSortUnit.pas.txt
QuickSortDemo.dpr.txt
QuickSortUnit.dfm.txt

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