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Mirror Tree

Tags : tree, geeksforgeeks, cpp, easy

Problem Statement - link #

Given a Binary Tree, convert it into its mirror.

Your Task: Just complete the function mirror() that takes node as paramter and convert it into its mirror. The printing is done by the driver code only.

Expected Time Complexity: O(N)
Expected Auxiliary Space: O(h) where h is height of the tree.

Examples #

Example 1:

Input:
      10
     /  \
    20   30
   /  \
  40  60
Output: 30 10 60 20 40
Explanation: The tree is
      10               10
    /    \  (mirror) /    \
   20    30    =>   30    20
  /  \                   /   \
 40  60                 60   40
The inroder traversal of mirror is
30 10 60 20 40.

Example 2:

Input:
      1
    /  \
   2    3
Output: 3 1 2
Explanation: The tree is
   1    (mirror)  1
 /  \    =>      /  \
2    3          3    2
The inorder of mirror is 3 1 2

Constraints #

Solutions #

class Solution {
  public:
    Node* nitish(Node* root){
        if(!root) return NULL;
        if(!root->left && !root->right) return root;
        Node* pleft = nitish(root->left);
        Node* pright = nitish(root->right);
        root->left = pright;
        root->right = pleft;
        return root;
    }
    // Function to convert a binary tree into its mirror tree.
    void mirror(Node* node) {
        // code here
        if(!node) return;
        nitish(node);
    }
};