// You should not need any additional header files, so please
// don't add any.

// For opendir(3)
#include <sys/types.h>
#include <dirent.h>

// For access(3)
#include <unistd.h>

// For printf(3)
#include <stdio.h>

// For exit(2)
#include <stdlib.h>

// For strncat(3), strncpy(3)
#include <string.h>


// Please make sure that you return a -1 if you weren't
// able to find any heap data in the filename that was
// passed.

int heap_space_used(char *filename)
{
  /* Your code goes below here */
  /* * * * * * * * * * * * * * */

  // Please put your code in this area, not elsewhere.
  

  /* * * * * * * * * * * * * * */
  /* Your code goes above here */
  
  return(-1);
}


// Please don't modify anything below this

int my_filter(const struct dirent *d)
{
  const char *str = d->d_name;
  if(str != NULL)
    {
      if( (*str >= '0') && (*str <= '9') )
        return(1);
    }
  return(0);
}

int main()
{
  struct dirent **namelist;
  chdir("/proc");

  int n = scandir(".", &namelist, my_filter, NULL);
  if(n < 0)
    {
      perror("Cannot scan directory /proc.");
      exit(1);
    }

  int index = 0;
  char pathname[256];

  int count = 0;
  float sum = 0; 

  while(index < n)
    {
      strncpy(pathname,"/proc/",256);
      strncat(pathname,namelist[index]->d_name,256);
      strncat(pathname,"/maps",256);
      int val = heap_space_used(pathname);
      if(val != -1)
	{
          printf("Usable result from %s.\n",pathname);
	  count++;
	  sum += val;
	}
      free(namelist[index]);
      index++;
    }
  free(namelist);

  printf("Processes read : %d, total heap used = %1.0f, average heap size = %10.2f\n",count,sum,sum/count);
}