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Invert Binary Tree

Certification: Basic Level Accuracy: 0% Submissions: 0 Points: 5

Write a C program to invert a binary tree. To invert a binary tree, we need to swap the left and right children for each node in the tree. The inverted tree should be a mirror reflection of the original tree.

Example 1
    
  
  • Input:


    Invert Binary Tree with Input of Root Node 4
    • 
  
  • Output:


     Invert Binary Tree with Output of Root Node 4
    • 
  
  • Explanation:
    
      
      
    • Step 1: Swap the left and right children of the root node (4): 2 and 7 are swapped
      • 
      
    • Step 2: Swap the left and right children of node 2: 1 and 3 are swapped
      • 
      
    • Step 3: Swap the left and right children of node 7: 6 and 9 are swapped
      • 
      
    • Step 4: The resulting tree is the mirror image of the original tree
      • 
    
    
  
    •
Example 2
    
  
  • Input:


     Invert Binary Tree with Input of Root Node 1
    • 
  
  • Output:


    Invert Binary Tree with Output of Root Node 1


    • 
  
  • Explanation:
    
      
      
    • Step 1: Swap the left and right children of the root node (1): 2 and 3 are swapped
      • 
      
    • Step 2: Node 2 has only one child (4), so after swapping, 4 becomes the left child
      • 
      
    • Step 3: Node 3 has no children, so no further action is needed
      • 
      
    • Step 4: The resulting tree is the mirror image of the original tree
      • 
    
    
  
    •
Constraints
    
  
  • The number of nodes in the tree is in the range [0, 100]
    • 
  
  • -100 ≤ Node.val ≤ 100
    • 
  
  • Time Complexity: O(n), where n is the number of nodes
    • 
  
  • Space Complexity: O(h), where h is the height of the tree (due to recursion stack)
    •
Binary TreeTech MahindraAdobe
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Hint
Solution

Solution Hints

    
  
  • Use a recursive approach to traverse the tree
    • 
  
  • For each node, swap its left and right children
    • 
  
  • Recursively invert the left subtree and right subtree
    • 
  
  • Handle leaf nodes and NULL pointers appropriately
    • 
  
  • The base case is when the node is NULL
    • 
  
  • The tree is built bottom-up as recursion unwinds
    •

Steps to solve by this approach:

 Step 1: Check if the root is NULL - if so, return NULL (base case)

 Step 2: Store the left child in a temporary variable

 Step 3: Assign the right child to be the new left child

 Step 4: Assign the temporary variable (original left child) to be the new right child

 Step 5: Recursively invert the left subtree

 Step 6: Recursively invert the right subtree

 Step 7: Return the root node with its subtrees inverted

Submitted Code :