Skip list jump Table C language code.

 

Code:

 

#include 
 
  #include 
  
   #include 
   
    #include 
    
     #define SKIP_LIST_INIT_LEVEL  5struct list_node_s;struct list_s;typedef struct list_node_s list_node_t;typedef struct list_s list_t;struct list_node_s {int key;void *value;int high;struct list_node_s **forward;};struct list_s {int level;struct list_node_s *header;};int random_level();list_t *new_list(int init_level);list_node_t *new_list_node(int high);void *find(list_t *l, int key);void insert(list_t *l, int key, void *value);void *delete_node(list_t *l, int key);void *destroy(list_t *l);int random_level(){int k = 0;//srand(time(NULL));while (rand() % 2) {k++;}return k;}list_t *new_list(int init_level) {list_t *l;l = malloc(sizeof(list_t));l->header = new_list_node(init_level);l->level = 0;l->header->key = -1;return l;}list_node_t *new_list_node(int high) {int i;list_node_t *n;n = malloc(sizeof(list_node_t));n->forward = malloc(high *sizeof(void *));n->high = high;for (i = 0; i < high; i++) {n->forward[i] = NULL;}return n;}void *find(list_t *l, int key){int k = l->level;list_node_t *n = l->header;while (n && k >= 0) {while(n->forward[k] && n->forward[k]->key <= key) {n = n->forward[k];}if (n->key == key) {return n->value;}k--;}return NULL;}void insert(list_t *l, int key, void *value){int insert_level;int k;size_t size;list_node_t *p, *q, *n;list_node_t **update;k = l->level;size = sizeof(void *) * (k + 1);update = malloc(size);p = q = l->header;while (q && k >= 0) {while (q->key < key) {p = q;if (q->forward[k]) {q = q->forward[k];}else {break;}}q = update[k] = p;//printf(level:%d->%d ,k, p->key);k--;}insert_level = random_level();if (insert_level > l->level ) {k = l->level++;insert_level = l->level;n = new_list_node(insert_level + 1);n->key = key;n->value = value;if (insert_level >= l->header->high) {list_node_t **l1, **l2;l1 = malloc(sizeof(void *) * (insert_level + 1));l2 = l->header->forward;memcpy(l1, l2, sizeof(void *) * insert_level);l1[insert_level] = NULL;l->header->forward = l1;free(l2);l->header->high++;l->header->forward[insert_level] = n;}else {l->header->forward[insert_level] = n;}}else {k = insert_level;n = new_list_node(k + 1);n->value = value;n->key = key;}//printf(key: %d update: , key);while (k >= 0) {p = update[k];//printf(%d , p->key);q = p->forward[k];p->forward[k] = n;n->forward[k] = q;k--;}//printf();free(update);}void *delete(list_t *l, int key) {int k = l->level;list_node_t *p, *q, *n;p = q = l->header;n = NULL;list_node_t **update;update = malloc(sizeof(void *) * (k + 1));while (q && k >= 0) {while (q->key < key) {p = q;if (q->forward[k]) {q = q->forward[k];}else {break;}}q = update[k] = p;k--;}if (update[0]->forward[0] && update[0]->forward[0]->key == key) {n = update[0]->forward[0];}else {free(update);return NULL;}k = n->high - 1;while (k >= 0) {p = update[k];p->forward[k] = n->forward[k];k--;}free(update);return n->value;}void show_list(list_t *l) {int k = l->level;list_node_t *n;n = l->header;while (k >= 0) {n = l->header;while (n) {printf(%d , n->key);n = n->forward[k];}printf();k--;}}int main(int argc, char *argv[]) {int k, i;list_t *l;void *ptr = &k;l = new_list(10);k = atoi(argv[1]);srand(time(NULL));i = k;printf(---------------);while (i > 0) {int key;key = rand() % k;insert(l, key, ptr);//show_list(l);i--;}i = k ;show_list(l);while (i > 0) {int key;void *p;key = rand() % k;p = find(l, key);if (p == NULL) {printf(key %d not found, key);}else {delete(l, key);printf(key %d found, key);}i--;}printf(--------------);//show_list(l);return 0;}