#include <stdbool.h>
typedef struct set *Set;

/** Creates a new empty set */
Set SetNew(void);

/** Free memory used by set */
void SetFree(Set set);

/** Inserts an item into the set */
void SetInsert(Set set, int item);

/** Deletes an item from the set */
void SetDelete(Set set, int item);

/** Checks if an item is in the set */
bool SetContains(Set set, int item);

/** Returns the size of the set */
int SetSize(Set set);

/** Displays the set */
void SetShow(Set set);