1 /* 以下代码为C++写成，下同*/
 2 Status SearchBST(BiTree T, KeyType key, BiTree f, BiTree &p){
 3   //在根指针T所指二元查找樹中递归地查找其關键字等於key的數據元素，若查找成功，
 4   //則指针p指向該數據元素節點，并返回TRUE，否則指针指向查找路徑上訪問的最後
 5   //一個節點并返回FALSE，指针f指向T的雙親，其初始调用值為NULL
 6   if(!T) { //查找不成功
 7     p=f;
 8     return false;
 9   }
10   else if (key == T->data.key) { //查找成功
11     p=T;
12     return true;
13   }
14   else if (key < T->data.key) //在左子樹中繼續查找
15     return SearchBST(T->lchild, key, T, p);
16   else //在右子樹中繼續查找
17     return SearchBST(T->rchild, key, T, p);
18 }

 1 /*当二元搜尋樹T中不存在关键字等于e.key的数据元素时，插入e并返回TRUE，否则返回FALSE*/
 2 Status InsertBST(BiTree *T, ElemType e){
 3       if(!T)
 4         {
 5             s = new BiTNode;
 6             s->data = e; s->lchild = s->rchild = NULL;
 7             T=s;    //被插節点*s为新的根结点
 8         }
 9       else if(e.key == p->data.key)
10         return false;//关键字等于e.key的数据元素，返回錯誤
11       if (e.key < p->data.key)
12     InsertBST(p->lchild, e);    //將e插入左子樹
13       else
14     InsertBST(p->rchild, e);    //將e插入右子樹
15       return true;
16  }

 1 Status DeleteBST(BiTree *T, KeyType key){
 2   //若二叉查找树T中存在关键字等于key的数据元素时，则删除该数据元素，并返回
 3   //TRUE；否则返回FALSE
 4   if(!T)
 5     return false;    //不存在关键字等于key的数据元素
 6   else{
 7     if(key == T->data.key) {     //  找到关键字等于key的数据元素
 8       return Delete(T);
 9     }
10     else if(key < T->data.key)
11       return DeleteBST(T->lchild, key);
12     else
13       return DeleteBST(T->rchild, key);
14   }
15 }
16
17 Status Delete(BiTree *p){
18   //该节点为叶子节点，直接删除
19   BiTree *q, *s;
20   if (!p->rchild && !p->lchild)
21   {
22       delete p;
23       p = NULL;
24   }
25   else if(!p->rchild){    //右子树空则只需重接它的左子树
26     q=p->lchild;
27     p->data = p->lchild->data;
28     p->lchild=p->lchild->lchild;
29     p->rchild=p->lchild->rchild;
30
31     delete q;
32   }
33   else if(!p->lchild){    //左子树空只需重接它的右子树
34     q=p->rchild;
35     p->data = p->rchild->data;
36     p->lchild=p->rchild->lchild;
37     p->rchild=p->rchild->rchild;
38
39     delete q;  }
40   else{    //左右子树均不空
41     q=p;
42     s=p->lchild;
43     while(s->rchild){
44       q=s;
45       s=s->rchild;
46     }    //转左，然后向右到尽头
47     p->data = s->data;    //s指向被删结点的“前驱”
48     if(q!=p)
49       q->rchild = s->lchild;    //重接*q的右子树
50     else
51       q->lchild = s->lchild;    //重接*q的左子树
52     delete s;
53   }
54   return true;
55 }

 1 def find_min(self):   # Gets minimum node (leftmost leaf) in a subtree
 2     current_node = self
 3     while current_node.left_child:
 4         current_node = current_node.left_child
 5     return current_node
 6
 7 def replace_node_in_parent(self, new_value=None):
 8     if self.parent:
 9         if self == self.parent.left_child:
10             self.parent.left_child = new_value
11         else:
12             self.parent.right_child = new_value
13     if new_value:
14         new_value.parent = self.parent
15
16 def binary_tree_delete(self, key):
17     if key < self.key:
18         self.left_child.binary_tree_delete(key)
19     elif key > self.key:
20         self.right_child.binary_tree_delete(key)
21     else: # delete the key here
22         if self.left_child and self.right_child: # if both children are present
23             successor = self.right_child.find_min()
24             self.key = successor.key
25             successor.binary_tree_delete(successor.key)
26         elif self.left_child:   # if the node has only a *left* child
27             self.replace_node_in_parent(self.left_child)
28         elif self.right_child:  # if the node has only a *right* child
29             self.replace_node_in_parent(self.right_child)
30         else: # this node has no children
31             self.replace_node_in_parent(None)

1 def traverse_binary_tree(node, callback):
2     if node is None:
3         return
4     traverse_binary_tree(node.leftChild, callback)
5     callback(node.value)
6     traverse_binary_tree(node.rightChild, callback)

 1 def build_binary_tree(values):
 2     tree = None
 3     for v in values:
 4         tree = binary_tree_insert(tree, v)
 5     return tree
 6
 7 def get_inorder_traversal(root):
 8     '''
 9     Returns a list containing all the values in the tree, starting at *root*.
10     Traverses the tree in-order(leftChild, root, rightChild).
11     '''
12     result = []
13     traverse_binary_tree(root, lambda element: result.append(element))
14     return result