Disjoint set data structure in c

Question

I want to implement the structure on the image in C language. But I have a problem because the 2 structures created call each other and therefore pose a problem how can I remedy it?

set data structure picture : Imgur link

liste set :

typedef struct liste_set
{
    set *head;
    set *tail;
} liste_set;

set :

typedef struct set set;
struct set
{
    int value;
    liste_set *liste;
    set *next;
};

Thank you for your help.

Note that with a circular list, pointer `tail` provides for O(1) access to tail&head - `head` is just `tail->next`. — greybeard, Oct 08 '22 at 20:14
@greybeard Wrong because ```tail->next``` is NULL for accessing head we need to do ```tail->liste->head``` but I see what you mean ;) — Stack Realtek, Oct 08 '22 at 22:35

score 1 · Accepted Answer · answered Oct 08 '22 at 17:52

All you have to do is have preceeding declerations so the compiler knows what set is even before you actually fully declare it.

// declare structs
struct liste_set;
struct set;

// typedef struct x to just x
typedef struct liste_set liste_set;
typedef struct set set;

// describe what the structs are
struct liste_set
{
    set *head;
    set *tail;
};

struct set
{
    int value;
    liste_set *liste;
    set *next;
};

Disjoint set data structure in c

1 Answers1