sort array of strings

This is a discussion on sort array of strings within the C Programming forums, part of the General Programming Boards category; Hey guys just wondering if u know how to sort an array of strings without using qsort and all of ...

  1. #1
    Musicman - Canora
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    sort array of strings

    Hey guys just wondering if u know how to sort an array of strings without using qsort and all of those. I dont get how all the swapping works and so on?

  2. #2
    Math wizard
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    All I can think of is to parse the strings until the null character is reached. That is, check to see if the given character has a value of 0. Once reached, use temporary strings (locally-defined would be one method) to store the contents. When done, write the strings in the order as you want. It's one method, but probably a lousy one.
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  3. #3
    CSharpener vart's Avatar
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    to compare strings - use strcmp
    to swap strings - strcpy (or if you can mange to build array of pointers to strings - just swap pointers)
    The first 90% of a project takes 90% of the time,
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  4. #4
    Registered User ssharish2005's Avatar
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    This is sample code snap which is used for sorting the array. Well, it just the compare and copy part of the whole sorting code. You should try using this code to build your whole sorting program.

    Code:
         if( strcmp(str[i], str[j]) > 0)            
              {
                  strcpy(temp,str[i]);
                  strcpy(str[i],str[j]);
                  strcpy(str[j],temp);
              }
    ssharish2005

  5. #5
    Frequently Quite Prolix dwks's Avatar
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    As vart was saying, if you pointers to strings (for example if the strings were dynamically allocated), you can just swap pointers.
    Code:
    char *p;
    
    if(strcmp(str[i], str[j]) > 0) {
        p = str[i];
        str[i] = str[j];
        str[j] = p;
    }
    Also see these pages for actual sorting algorithms.
    http://cprogramming.com/tutorial.html#algorithms
    http://en.wikipedia.org/wiki/Sorting_algorithm
    http://en.wikipedia.org/wiki/Category:Sort_algorithms
    dwk

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