/*------------------------------------------------------------------*/
/* sort6.c (The Standard qsort Function, Casting of Function        */
/*          Pointers)                                               */
/*------------------------------------------------------------------*/

#include <stdio.h>
#include <stdlib.h>
#include <assert.h>

#define INITIAL_LENGTH 2

/*------------------------------------------------------------------*/

static int compareDouble(double *pdItem1, double *pdItem2)

/* Return -1, 0, or 1 depending upon whether *pdItem1 is
   less than, equal to, or greater than *pdItem2, respectively. */

{
   if (*pdItem1 < *pdItem2) return -1;
   if (*pdItem1 > *pdItem2) return 1;
   return 0;
}

/*------------------------------------------------------------------*/

int main(int argc, char *argv[])

/* Read numbers from stdin, and write them in ascending order to 
   stdout. */

{
   double *pdArray;
   int iNumberCount;
   int iLength;
   double dNumber;
   int i;

   /* Dynamically allocate an array. */

   iLength = INITIAL_LENGTH;
   pdArray = (double*)calloc((size_t)iLength, sizeof(double));
   assert(pdArray != NULL);

   /* Read the numbers into the array. */

   iNumberCount = 0;
   while (scanf("%lf", &dNumber) != EOF)
   {
      if (iNumberCount == iLength)
      {
         iLength *= 2;
         pdArray = (double*)realloc(pdArray, iLength * sizeof(double));
         assert(pdArray != NULL);
      }
      pdArray[iNumberCount] = dNumber;
      iNumberCount++;
   }

   /* Sort the array. */

   qsort(pdArray, (size_t)iNumberCount, sizeof(double), 
         (int(*)(const void*, const void*))compareDouble);

   /* Write the numbers from the array. */

   for (i = 0; i < iNumberCount; i++)
      printf("%g\n", pdArray[i]);

   /* Free the array. */

   free(pdArray);

   return 0;
}