Quicker then QuickSort???

From: madler (anonymous_at_discussions.microsoft.com)
Date: 05/10/04 

Date: Mon, 10 May 2004 08:36:07 -0700

Hi.

I might be a bit niave here but I was looking over a quicksort implementation (provide by compuware as a sample for DevPartner Profiler community edition) and I thought that I could do better then that. So I implemented my own simple sorting algoritim and it seems to run twice as fast as the quicksort.

So my question is - What is the catch with my algorithim - why do all libraries include the very complex QuickSort when something as simple as what I did is not used. I am sure that people have explored the same method before. Does anyone know what it's shortcomes are?

Here is the method:

                        int lval,lpos;
                        int hval,hpos;
                        lpos = 0;
                        hpos = 0;
                        lval = 1000000;
                        hval = 0;
                        for (int i = 0 ;i<(numElems /2);i++)
                        {
                                
                                flag = false;
                                int j;
                                lval = hval;
                                hval = 0;
                                for (j = i;j<((numElems -i)-1);j++)
                                {
                                        int c = Elements[j];
                                        if (c < lval)
                                        {
                                                lpos = j;
                                                lval = c;
                                        
                                        }
                                        if (c > hval)
                                        {
                                                hpos = j;
                                                hval = c;
                                                
                                        }
                                }
                                
                                SwapEm(i,lpos);
                                SwapEm(j,hpos);
                                
                        }

Thanks

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