Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <pre><code>#include &lt;stdlib.h&gt; #include &lt;stdio.h&gt; #include &lt;string.h&gt; typedef struct { unsigned char message[100]; // string to be sorted // (totally arbitrary length) unsigned char sortOrder[256]; // string containing ASCII chars // in their sort order } Pair; unsigned char rank[256]; // rank of each ASCII character // qsort() comparison function int sortByRank(const void *a, const void *b) { return ((int)rank[*(signed char *)a] - (int)rank[*(signed char *)b]); } // Creates an array by which a character's relative position can be found // solely from its value. Characters of rank 0 will appear first when sorted. // Characters not specified by sortOrder will appear first, since rank is // global and automatically initialized to zeros. void initRank(Pair pair) { int i; for (i = 0; i &lt; strlen(pair.sortOrder); i++) rank[pair.sortOrder[i]] = i; return; } int main() { // Create an example pair. Spaces will be the first characters in the // sorted result. Pair pair; strcpy(pair.message, "this is a test message (123)."); strcpy(pair.sortOrder, " 321abcdefghijklm.nopqrstuvwxyz()"); // In this solution, initRank() will need to be called any time the // sortOrder is changed. initRank(pair); // Sort using the global rank array set by initRank() qsort(pair.message, strlen(pair.message), sizeof(char), sortByRank); printf("Sorted message: %s\n", pair.message); // Output: // Sorted message: 321aaeeeghiim.sssssttt() return 0; } </code></pre> <p>Since rank[] is global, this isn't as elegant as might be, but the above solution generally demonstrates how to make use of C's sorting function to do a custom sort based on a second string in a fairly straightforward manner.</p>
    singulars
    1. This table or related slice is empty.
    1. POhow to sort string array in ascending order using sort function in C
      singulars
      1. PTQuestion
    1. PTAnswer
    1. USDavid Duncan
    1. USDavid Duncan
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    1. COYou might make rank[] an int array and define your cmp as simply `return rank[*(char *)a] - rank[*(char*)b];` But +1
      singulars
      1. PO
      1. USPaul Hankin
    2. CO@Anonymous: Thanks, I've simplified the comparison function per your suggestion.
      singulars
      1. PO
      1. USDavid Duncan
    3. COYour simplification is wrong if char is unsigned.
      singulars
      1. PO
      1. USPaul Hankin
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload