#ifndef SPLIST_H
#define SPLIST_H
#include "util.h"
#include "list.h"

/* A sparse list is a list with its "inverse list".  This can be used
   to determine if a number belongs to a sparse list at constant
   time. */

typedef struct splist_s splist;

splist *new_splist();

/* A sparse list is of fixed size. */
unsigned char init_splist(splist *s, NUM size);

P_ATTR NUM splist_len(CCR_MOD(splist *) s);

/* NOTE: The returned list is owned by the original splist, so don't
   destroy that list or do anything that should not be done. */
P_ATTR List *splist_ls(CCR_MOD(splist *) s);

/* We assume that elements of a sparse list are of type NUM. */
unsigned char add_to_splist(splist *s, NUM element);

/* resetting a sparse list means to set its length to 0 */
void reset_splist(splist *s);

/* Constant time operation */
unsigned char splist_is_member(splist *s, NUM element);

void print_splist(splist *s);

void destroy_splist(splist *s);

#endif