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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: Sort char array
Date: Wed, 09 Oct 2019 09:43:02 -0700
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Tim Rentsch <tr.17687@z991.linuxsc.com> writes:

> John Bode <jfbode1029@gmail.com> writes:
>
>> On Monday, October 7, 2019 at 7:09:29 PM UTC-5, Ben Bacarisse wrote:
>>
>>> John Bode <jfbode1029@gmail.com> writes:
>>>
>>>> On Friday, October 4, 2019 at 11:59:39 AM UTC-5, DFS wrote:
>>>>
>>>>> 1  void psort(int n,char *x[]) {
>>>>> 2    char *temp;
>>>>> 3      for(i=0;i<n;i++) {
>>>>> 4        for(j=0;j<n;j++) {
>>>>> 5          if(strcasecmp(x[j],x[i])>0) {
>>>>> 6            temp = x[i];
>>>>> 7            x[i] = x[j]);
>>>>> 8            x[j] = temp;
>>>>> 9          }
>>>>> 10       }
>>>>> 11     }	
>>>>> 12  }
>>>>>
>>>>>
>>>>> This works, but is very slow.  Like 6 seconds to sort an array of 10,000
>>>>> elements.
>>>>>
>>>>> What am I doing wrong?
>>>>
>>>> You're using a bubble sort (which is O(n^2)) and you've implemented it
>>>> slightly incorrectly,
>>>
>>> It's not bubble sort at all.  (I thought it was at first, but I simply
>>> had not looked properly.)  It tests every possible pair of values
>>> (twice!) and swaps them if they are out of order.
>>
>> As I said, it's a bubble sort that's been implemented slightly
>> incorrectly.  It would be correct if j started from i instead of 0.
>
> Try coding that and see if it gives the desired behavior.
> (Hint: it doesn't.)

Sorry, my bad.  The description and code is so awful I got
confused about what it wasn't doing.