Quick Sort : array of pointers to structures

#include "stdio.h"
#include "string.h"
#include "stdlib.h"

struct node
{
char *str;
};

/* compare function for qsort */
static int cmpr(const void *a, const void *b);

int main(void)
{
struct node **strarray = NULL;
int i = 0, count = 0;
char line[1024];

while(fgets(line, 1024, stdin) != NULL)
{
/* add ONE element to the array */
strarray = (struct node **)realloc(strarray, (count + 1) * sizeof(struct node *));

/* allocate memory for ONE `struct node` */
strarray[count] = (struct node *)malloc(sizeof(struct node));

/* copy the data into the new element (structure) */
strarray[count]->str = strdup(line);
count++;
}

/* before sorting ... */
printf("Before:\n");
for(i = 0; i < count; i++)
{
printf("[%d]->str: %s", i, strarray[i]->str);
}

/* qsort array of structures */
qsort(strarray, count, sizeof(*strarray), cmpr);

/* after sorting ... */
printf("\n--\nAfter:\n");
for(i = 0; i < count; i++)
{
printf("[%d]->str: %s", i, strarray[i]->str);
}

/* free all strarray elements */
for(i = 0; i < count; i++)
{
free(strarray[i]->str);
free(strarray[i]);
i++;
}
free(strarray);

return 0;
}

/* compare function for qsort */
static int cmpr(const void *a, const void *b)
{
struct node * const *one = a;
struct node * const *two = b;

return strcmp((*one)->str, (*two)->str);
}

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