Practice_4: BST class

 

//missing some definition hereclass BSTree: protected Tree{protected:TreeNode* FindMin(TreeNode* head, TreeNode** gp);TreeNode* FindMax(TreeNode* head, TreeNode** gp);void DFS(TreeNode* head);public:BSTree():Tree(2){ }~BSTree();bool IsEmpty(void){ return (root == NULL); }TreeNode* GetRoot(void) { return root; }void BuildTree(KeyType keyVal, void* item = NULL);void* Delete(KeyType keyVal);void Insert(KeyType keyVal, void* item = NULL);void* FindMinItem(void) { return FindMin(root, NULL)->item[order - 2]; }void* FindMaxItem(void) { return FindMax(root, NULL)->item[order - 2]; }void* Find(KeyType keyVal);void Print(void) { DFS(root); printf("/n"); }void test(void);};//====================================== Tree ClassBSTree::~BSTree(){while(Delete(-1000)) ;}void BSTree::BuildTree(KeyType keyVal,void* item){Insert(keyVal, item);}void* BSTree::Delete(KeyType keyVal){TreeNode* ptr = root;TreeNode* parent = root;int index = -1; //rootvoid* item = NULL;if(keyVal == -1000 && ptr) //Assume that -1000 is invalid, it means that delete the rootkeyVal = ptr->key[order - 2];while(ptr){if(ptr->key[order - 2] < keyVal){parent = ptr;ptr = ptr->child[order - 1];index = order -1;}else if(ptr->key[order - 2] > keyVal){parent = ptr;ptr = ptr ->child[order - 2];index = order -2;}else if(ptr->child[order - 2]&&ptr->child[order - 1]){parent = ptr;TreeNode* minInRight = FindMin(ptr->child[order -1], &parent); //find the min in the right nodeptr->key[order - 2] = minInRight->key[order - 2];item = ptr->item[order - 2];ptr->item[order - 2] = minInRight->item[order - 2];if(parent == ptr){parent->child[order - 1] = minInRight->child[order - 1];}else{parent->child[order - 2] = minInRight->child[order - 1];}delete minInRight;break;}else{if(!ptr->child[order - 1])if(index < 0) //it's rootroot = ptr->child[order - 2];elseparent->child[index] = ptr->child[order - 2];else if(!ptr->child[order - 2])if(index < 0)root = ptr->child[order - 1];elseparent->child[index] = ptr->child[order - 1];item = ptr->item[order - 2];delete ptr;break;}}return item;}void BSTree::Insert(KeyType keyVal,void* item){TreeNode* newNode = new TreeNode(order, item, keyVal);TreeNode* temp= root;TreeNode* parent= root;int index;ASSERT(newNode);if(!root){root = newNode;return;}while(temp != NULL){if(temp->key[order-2] > keyVal){parent = temp;temp = temp->child[order-2];index = order - 2;}else if(temp->key[order-2] < keyVal){parent = temp;temp = temp->child[order-1];index = order - 1;}}parent->child[index] = newNode;}TreeNode* BSTree::FindMin(TreeNode* head, TreeNode** gp){TreeNode* ptr = head;TreeNode* parent = head;TreeNode* grandparent = NULL;if(gp){parent = *gp;grandparent = *gp;}while(ptr){grandparent = parent;parent = ptr;ptr = ptr->child[order - 2];}if(gp){*gp = grandparent;}return parent;}TreeNode* BSTree::FindMax(TreeNode* head, TreeNode** gp){TreeNode* ptr = head;TreeNode* parent = head;TreeNode* grandparent = NULL;if(gp){parent = *gp;grandparent = *gp;}while(ptr){grandparent = parent;parent = ptr;ptr = ptr->child[order - 1];}if(gp){*gp = grandparent;}return parent;}void* BSTree::Find(KeyType keyVal){TreeNode* ptr = root;void* item = NULL;while(ptr){if(ptr->key[order - 2] < keyVal)ptr = ptr->child[order - 1];else if(ptr->key[order - 2] > keyVal)ptr = ptr->child[order - 2];else{item = ptr->item[order - 2];break;}}return item;}void BSTree::DFS(TreeNode* head){if(!head)return;printf("%d ", head->key[order - 2]);DFS(head->child[order - 2]);DFS(head->child[order - 1]);}void BSTree::test(void){static int element[7] = {6,2,8,1,5,3,4};for(int i=0; i<7; i++){BuildTree(element[i]);printf("%d ",FindMin(root, NULL)->key[0]);}printf("/n");Print();while(!IsEmpty()){printf("%d /n", *((int*)Delete(2)));printf("%d /n", *((int*)Delete(5)));printf("%d F/n", *((int*)Find(3)));if(!Find(5)){printf("not found/n");}printf("%d Min/n",*((int*)FindMinItem()));printf("%d Max/n",*((int*)FindMaxItem()));printf("%d /n", *((int*)Delete(1)));printf("%d Min@/n",FindMin(root, NULL)->key[0]);printf("%d /n", *((int*)Delete(3)));printf("%d Min@/n",FindMin(root, NULL)->key[0]);printf("%d /n", *((int*)Delete(4)));printf("%d Min@/n",FindMin(root, NULL)->key[0]);printf("%d /n", *((int*)Delete(6)));printf("%d Min@/n",FindMin(root, NULL)->key[0]);printf("%d /n", *((int*)Delete(8)));}} 

 

二叉搜索数的指针实现；

 

fight on !!