数据结构之树和二叉树---二叉树的基本操作

问题：二叉树的基本操作函数，主要内容为二叉树的数据结构，初始化二叉树，销毁二叉树，创建二叉树，求二叉树深度，二叉树双亲节点，二叉树左孩子，二叉树右孩子，二叉树左兄弟，二叉树右兄弟，根据名称查找二叉树节点，插入节点及删除节点

//二叉树数据结构

typedef struct BiTNode{TElemType data;struct BiTNode* lchild, * rchild;}BiTNode, *BiTree;

//初始化二叉树

FILE* BTEF;BiTree InitBiTree(){BiTree bt;bt = NULL;BTEF = fopen("BiTreeElem.txt", "r");return bt;}

//销毁二叉树

void DestroyBiTree(BiTree bt){if(bt){DestroyBiTree(bt->lchild);DestroyBiTree(bt->rchild);free(bt);}        fclose(BTEF);}

//创建二叉树

//通过文本文件读取二叉树节点信息，空节点以“0”表示，节点顺序为二叉树先序遍历顺序

void CreatBiTree(BiTree *bt){char node;fread(&node, sizeof(char), 1, BTEF);if(node==' ')fread(&node, sizeof(char), 1, BTEF);if(node=='0')*bt = NULL;else{if(*bt==NULL)*bt = (BiTree) malloc (sizeof(BiTNode));(*bt)->data = node;(*bt)->lchild = NULL;(*bt)->rchild = NULL;CreatBiTree(&(*bt)->lchild);CreatBiTree(&(*bt)->rchild);}}

//文本信息样例

/*A B D 0 F 0 0 0 C 0 E G 0 0 0*/

//求二叉树深度

int BiTreeDepth(BiTree bt){int leftBTDepth, rightBTDepth;if(bt==NULL)return 0;else{leftBTDepth = BiTreeDepth(bt->lchild)+1;rightBTDepth = BiTreeDepth(bt->rchild)+1;return leftBTDepth>rightBTDepth? leftBTDepth:rightBTDepth;}}

//二叉树双亲节点

//查找信息的依据是节点名称，返回值为节点指针

BiTNode* BiTreeParent(BiTree bt, TElemType elem){BiTNode* btn;if(bt!=NULL){if (bt->lchild!=NULL){if(bt->lchild->data!=elem){btn = BiTreeParent(bt->lchild,elem);if(btn!=NULL)return btn;}elsereturn bt;}if (bt->rchild!=NULL){if(bt->rchild->data!=elem)return BiTreeParent(bt->rchild,elem);elsereturn bt;}}return NULL;}

//二叉树左孩子

BiTNode* LeftChild(BiTree bt, TElemType elem){BiTNode* tbn;if(bt!=NULL){if(bt->data==elem)return bt->lchild;else{tbn = LeftChild(bt->lchild, elem);if(tbn!=NULL)return tbn;return LeftChild(bt->rchild, elem);}}return NULL;}

//二叉树右孩子

BiTNode* RightChild(BiTree bt, TElemType elem){BiTNode* tbn;if(bt!=NULL){if(bt->data==elem)return bt->rchild;else{tbn = RightChild(bt->lchild, elem);if(tbn!=NULL)return tbn;return RightChild(bt->rchild, elem);}}return NULL;}

//二叉树左兄弟

BiTNode* LeftSibling(BiTree bt, TElemType elem){BiTNode *tbn;if(bt==NULL)return NULL;if (bt->rchild!=NULL){if(bt->rchild->data==elem)return bt->lchild;else{tbn = LeftSibling(bt->rchild, elem);if(tbn!=NULL)return tbn;}} return LeftSibling(bt->lchild, elem);}

//二叉树右兄弟

BiTNode* RightSibling(BiTree bt, TElemType elem){BiTNode *tbn;if(bt==NULL)return NULL;if (bt->lchild!=NULL){if(bt->lchild->data==elem)return bt->lchild;else{tbn = RightSibling(bt->lchild, elem);if(tbn!=NULL)return tbn;}}return RightSibling(bt->rchild, elem);}

//根据名称查找二叉树节点

BiTNode* SearchNode(BiTree bt, TElemType elem){BiTNode *tbn;if(bt==NULL)return NULL;if(bt->data==elem)return bt;else{tbn = SearchNode(bt->lchild, elem);if(tbn!=NULL)return tbn;return SearchNode(bt->rchild, elem);}return NULL;}

//插入节点

//插入节点时，需要插入节点或子树指针，插入节点双亲名称，及作为双亲节点的左孩子还是右孩子

int InsertChild(BiTree bt, TElemType elem, int LR, BiTree child){BiTNode* pn;if (!child||!bt||(LR!=0&&LR!=1))return -1;if (LR==0){pn = LeftChild(bt, elem);if(pn==NULL)SearchNode(bt, elem)->lchild = child;elsereturn -1;} else{pn = RightChild(bt, elem);if(pn==NULL)SearchNode(bt, elem)->rchild = child;elsereturn -1;}return 0;}

//删除节点

int DeleteChild(BiTree bt, TElemType elem, int LR){BiTNode* pn;if(!bt||(LR!=0&&LR!=1))return -1;if(LR==0){pn = LeftChild(bt, elem);if(pn!=NULL){DeleteChild(bt, pn->data, 0);DeleteChild(bt, pn->data, 1);free(pn);if((pn=SearchNode(bt,elem))!=NULL)pn->lchild = NULL;}}else{pn = RightChild(bt, elem);if(pn!=NULL){DeleteChild(bt, pn->data, 0);DeleteChild(bt, pn->data, 1);free(pn);if((pn=SearchNode(bt,elem))!=NULL)pn->rchild = NULL;}}}