函数指针

排序函数qsort

#include <stdio.h>

int compare (const void * a, const void * b)
{
    return *(int *)a - *(int *)b;
}
int main (void)
{
    int arr[15] = {999, 23, 39, 23, 199, 1, 23, -432, 1, 0, 23, -32, 235, 13, 2};

    int i;
    for (i = 0; i < 15; i++)
    {
        printf ("%5d ", arr[i]);
    }
    printf ("\n");

    qsort (arr, 15, sizeof (int), compare);

    for (i = 0; i < 15; i++)
    {
        printf ("%5d ", arr[i]);
    }
    printf ("\n");
}