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Efficient method to sort a CPtrarray?

Posted on 2006-03-22
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What is the Efficient method to sort a CPtrarray in c++?
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Question by:XPUSR
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DanRollins earned 200 total points
ID: 16261557
Use qsort... as described here:
    Q216858
    How to use the quick-sort function to sort MFC CArray-derived classes on the MFC and Visual C++ run-time library
    http://support.microsoft.com/support/kb/articles/Q216/8/58.ASP

You will of course need to sort not on the *value* of the pointer itself, but on the value of the data to which each item points.  You write that logic into your Compare() function.

-- Dan
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by:PaulCaswell
ID: 16262271
Hi XPUSR,

It depends on what you mean by efficient and a good deal on the type of data. For example, if most of the values are the same except just a few or most of them are already sorted then, believe it or not, bubblesort would be your best bet, with the normal tuning techniques.

Tell us a bit more about the data. Whats in it? How much does it vary? Can you add them one-at-a-time or do you get them in one big block? Etc ...

Paul
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by:AndyAinscow
ID: 16266432
What is efficient.
The bubble sort is very easy to code but takes a lot of time to sort compared to more advanced techniques.
However, if the array has, say, 8 pointers would the end user really notice it takes 0.001 seconds longer to execute?

(Bubble sort is just go through the array and swap adjacent items if they are not in order.  You keep doing that until no swaps are made.)
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by:XPUSR
ID: 16284890
Thanks for the suggestions. How about conveting it to a vector and using the stl sort. How does this compare? The data in an array of stock performances.
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