Binary tree Image (c + + version) __c++

Topic:

Given the source binary tree, the design algorithm realizes its mirror image.

Ideas:

For the problem of binary tree, it is necessary to consider the non recursive implementation of the recursive method.

This is a good recursive implementation, for the first node traversal, each exchange its left and right subtree. Then recursively calls to its subtree.

For non-recursive implementations, you need to use a secondary stack to hold the header nodes. (Sequence traversal)

Note:

The binary tree node is defined as follows:

typedef int DATATYPE;

struct Node

{

DataType Val;

struct Node *left;

struct Node *right;

Node (DataType _val):

Val (_val), left (null), right (null) {}

};

Paste Code:

void Mirror (TreeNode *proot) {if (0) {//recursive implementation if (Proot = = NULL) {
            Return
            } TreeNode *temp;
            temp = proot->left;
            Proot->left = proot->right;

            Proot->right = temp;
            Mirror (Proot->left);
        Mirror (Proot->right);
            
            else {//non-recursive implementation (requires the use of a secondary stack) stack<treenode*> Stk;
            if (Proot = = NULL) {return;
            
            } stk.push (Proot); If the stack is not empty the description also needs to traverse the while (!stk.empty ()) {//Get the current traversal subtree header node TreeNode *
                Head = Stk.top ();
                
                Stk.pop ();
                    Any subtree of the head node is not empty and needs to be exchanged if (Head->left | | head->right) {TreeNode *temp;
        temp = head->left;            Head->left = head->right;
                Head->right = temp; //Press into the new head node if (head->left) {Stk.push (head-&gt
                ; left);
                } if (head->right) {Stk.push (head->right);
    }} return; }