#include <stdio.h>

#include <stdlib.h>

#include <ctype.h>



int main(void)

{

  double *values = NULL;     /* Pointer to memory holding data values       */

  double *temp = NULL;       /* Pointer to newly allocated memory           */

  double sum = 0.0;          /* Sum of values                               */

  int capacity = 0;          /* Maximum number of values that can be stored */

  int increment = 5;         /* Capacity increment for dynamic allocation   */

  int count = 0;             /* Number of values read                       */

  char answer = 'n';



  do

  {

    if(count == capacity)    /* Check if there is spare memory */

    {

      capacity += increment; /* Increase the capacity of memory by increment */

      temp = (double*)malloc((capacity)*sizeof(double)); /* and allocate it  */

      if(!temp)              /* If memory was not allocated */

      {                      /* Output a message  and end   */

        printf("Memory allocation failed. Terminating program.");

        exit(1);

      }

      if(!values)            /* Are there any values?                  */

        values = temp;       /* No - so just copy address of new memory */

      else                   /* Yes - so copy data from old to new      */

      {

        for(int i = 0 ; i<count ; i++)

          *(temp + i) = *(values + i);

        free(values);        /* Free the old memory */

        values = temp;       /* Copy address of new */

      }

      temp = NULL;           /* Reset pointer       */

    }



    printf("Enter a value: ");

    scanf("%lf", values+count++);



    printf("Do you want to enter another(y or n)? ");

    scanf(" %c", &answer);

  }while(tolower(answer) == 'y');



  /* Now sum the values */

  for(int i = 0 ; i<count ; i++)

    sum += *(values+i);



  /* Output the average */

  printf("\n The average of the the values you entered is %.2lf.\n", sum/count);

  free(values);     /* We are done - so free the memory */

  return 0;

}