二项队列实现文件C语言

/*binomial-queue.c -- 二项队列实现文件*/#include "binomial-queue.h"/*局部函数声明*/static SubTree Combine_Trees (SubTree t1, SubTree t2) ;static Node * Make_Node (const Item item) ;static void Recursively (const SubTree t, void (* pfun) (const Item item)) ;/*接口函数定义*/int InitializeBinQueue (BinQueue * const pbq, const int size){int i ;if (size <= 0)return 0 ;*pbq = (struct binqueue *) malloc (sizeof (struct binqueue)) ;if (NULL == *pbq)return 0 ;(*pbq) -> forest = (SubTree *) malloc (sizeof (SubTree) * size) ;if (NULL == (*pbq) -> forest){free (*pbq) ;return 0 ;}for (i = 0; i < size; i++)(*pbq) -> forest[i] = NULL ;(*pbq) -> size = size ;(*pbq) -> current = 0 ;return 1 ;}int BinQueueIsEmpty (const BinQueue bq){return 0 == bq -> current ;}BinQueue Merge (BinQueue bq1, BinQueue bq2){BinQueue temp ;SubTree t1, t2, carry = NULL ;int i, j, ct, index = 0 ;//此处的检测, 很重要.if (bq1 == bq2)return bq1 ;if (bq1 -> current + bq2 -> current > bq1 -> size)return bq1 ;bq1 -> current += bq2 -> current ;//保障 bq1 -> current > bq2 -> current-->if (bq1 -> current < bq2 -> current){temp = bq1 ;bq1 = bq2 ;bq2 = temp ;}//这样就可以通过下面的 bq2 所有子树都已被合并过的条件检测有//效地避免当 bq2 -> current 很小的时候将造成的太多次不必要的条件检测-->for (i = 0, j = 1, ct = 0; j <= bq1 -> current; i++, j *= 2){t1 = bq1 -> forest[i] ;//以下判断是为了应对Insert的情况, 因为我在Insert时只分配了1棵子树的空间if (1 == index)t2 = NULL ;else if (1 == bq2 -> size){index = 1 ;t2 = bq2 -> forest[i] ;}elset2 = bq2 -> forest[i] ;//这个方法真的很巧妙, 开了眼界switch (!!t1 + 2 * !!t2 + 4 * !!carry){//no treescase 0 :break ;//only bq1case 1 :if (ct == bq2 -> size){Release (bq2) ;return bq1 ;}break ;//only bq2case 2 :bq1 -> forest[i] = t2 ;bq2 -> forest[i] = NULL ;ct++ ;break ;//only carrycase 4 :bq1 -> forest[i] = carry ;carry = NULL ;break ;//bq1 and bq2case 3 :carry = Combine_Trees (t1, t2) ;bq1 -> forest[i] = bq2 -> forest[i] = NULL ;ct++ ;break ;//bq1 and carrycase 5 :carry = Combine_Trees (t1, carry) ;bq1 -> forest[i] = NULL ;break ;//bq2 and carrycase 6 :carry = Combine_Trees (t2, carry) ;bq2 -> forest[i] = NULL ;ct++ ;break ;//all therecase 7 :bq1 -> forest[i] = carry ;carry = Combine_Trees (t1, t2) ;bq2 -> forest[i] = NULL ;break ;}}return bq1 ;}BinQueue Insert (BinQueue bq, const Item item){BinQueue temp ;int size = 1 ;if (bq -> size == bq -> current)return bq ;if (!InitializeBinQueue (&temp, size)){free (temp -> forest) ;free (temp) ;return bq ;}temp -> forest[0] = Make_Node (item) ;if (NULL == temp -> forest[0])// 话说这个位置原先有一个";"{free (temp -> forest[0]) ;free (temp) ;return bq ;} temp -> current = 1 ;bq = Merge (bq, temp) ;return bq ;}Item DeleteMin (BinQueue bq){BinQueue deleted_queue ;SubTree deleted_tree, old_root ;Item min ;int i, j, size, min_index ;if (BinQueueIsEmpty (bq))return -INFINITY ;min = INFINITY ;for (i = 0, size = bq -> size; i < size; i++){if (bq -> forest[i] && bq -> forest[i] -> item < min){min = bq -> forest[i] -> item ;min_index = i ;}}if (INFINITY == min)return INFINITY ;deleted_tree = bq -> forest[min_index] ;old_root = deleted_tree ;deleted_tree = deleted_tree -> left ;free (old_root) ;InitializeBinQueue (&deleted_queue, (1 << min_index) - 1) ;for (j = min_index - 1; j >= 0; j--){deleted_queue -> forest[j] = deleted_tree ;deleted_tree = deleted_tree -> nextsibling ;deleted_queue -> forest[j] -> nextsibling = NULL ;}bq -> forest[min_index] = NULL ;bq -> current -= deleted_queue -> current + 1 ;bq = Merge (bq, deleted_queue) ;return min ;}void Traversal (const BinQueue bq, void (* pfun) (const Item item)){int i, size ;for (i = 0, size = bq -> size; i < size; i++)if (bq -> forest[i])Recursively (bq -> forest[i], pfun) ;}void Release (const BinQueue bq){int i, size ;for (i = 0, size = bq -> size; i < size; i++){if (bq -> forest[i])free (bq -> forest[i]) ;}free (bq) ;}/*局部函数定义*/static SubTree Combine_Trees (SubTree t1, SubTree t2){if (t1 -> item > t2 -> item)return Combine_Trees (t2, t1) ;//话说这个地方的 t1 原来是 t2, 真不知道我这一天都在想些什么t2 -> nextsibling = t1 -> left ;t1 -> left = t2 ;return t1 ;}static Node * Make_Node (const Item item){Node * new_node ;new_node = (Node *) malloc (sizeof (Node)) ;if (NULL == new_node)return NULL ;new_node -> item = item ;new_node -> left = new_node -> nextsibling = NULL ;return new_node ;}static void Recursively (const SubTree t, void (* pfun) (const Item item)){if (t -> left)Recursively (t -> left, pfun) ;if (t -> nextsibling)Recursively (t -> nextsibling, pfun) ;(* pfun) (t -> item) ;}