Texas Instruments TMS320C2x, Руководство пользователя

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qsort
7-43 Run-Time-Support Functions
Array Sort
qsort
Syntax #include <stdlib.h>
void qsort (void *base, size_t nmemb, size_t size, int (*compar)
(const void *, const void *));
Defined in qsort.c in rts.src
Description The qsort function sorts an array of nmemb members. Argument base points
to the first member of the unsorted array; argument size specifies the size of
each member.
This function sorts the array in ascending order.
Argument compar points to a function that compares key to the array ele-
ments. The comparison function should be declared as:
int cmp(ptr1, *ptr2)
void *ptr1, *ptr2;
The cmp function compares the objects that ptr1 and ptr2 point to and returns
one of the following values:
< 0 if *ptr1 is less than *ptr2
0 if *ptr1 is equal to *ptr2
> 0 if *ptr1 is greater than *ptr2
Example In the following example, a short list of integers is sorted with qsort.
#include <stdlib.h>
int list[ ] = {3, 1, 4, 1, 5, 9, 2, 6};
int idiff (const void *, const void *);
main( )
{
qsort (list, 8, 1, idiff);
/* after sorting, list[ ]= ={ 1, 1, 2, 3, 4, 5, 6, 9} */
}
int idiff (const void *i1, const void *i2)
{
return *(int *)i1 − *(int *)i2;