#include <search.h>struct node {struct node *next;struct node *prev;};void insque(void *element, void *pred){struct node *e = element;struct node *p = pred;if (!p) {e->next = e->prev = 0;return;}e->next = p->next;e->prev = p;p->next = e;if (e->next)e->next->prev = e;}void remque(void *element){struct node *e = element;if (e->next)e->next->prev = e->prev;if (e->prev)e->prev->next = e->next;}