Deletion of empty map bug fix

Author: mmoschenskikh

linked_hash_map.c

@@ -18,6 +18,10 @@ struct LinkedHashMap *createHashMap() {
 
 void deleteMap(struct LinkedHashMap *map) {
  struct Entry *elem = map->head;
+ if (elem == NULL) {
+ free(map);
+ return;
+ }
  struct Entry *next = map->head->after;
  while (next != NULL) {
  free(elem);