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Binary Tree Traversals

Certification: Advanced Level Accuracy: 33.33% Submissions: 6 Points: 15

ite a Python function that performs inorder, preorder, and postorder traversal of a binary tree. Each traversal should return a list of node values in the order they are visited.

Example 1
    

  • Input:
    [1,null,2,3]
    Tree:

    Binary Tree Traversals with maximum value 3


    • 

  • Output:
    Inorder: [1, 3, 2]
    Preorder: [1, 2, 3]
    Postorder: [3, 2, 1]
    •
Example 2
    

  • Input:
    [1,2,3,4,5]
    Tree:

    Binary Tree Traversals with maximum value 5

    • 

  • Output:
    Inorder: [4, 2, 5, 1, 3]
    Preorder: [1, 2, 4, 5, 3]
    Postorder: [4, 5, 2, 3, 1]
    •
Constraints
    

  • 0 ≤ nodes ≤ 100
    • 

  • -100 ≤ Node.val ≤ 100
    • 

  • Time Complexity: O(n)
    • 

  • Space Complexity: O(h)
    •
RecursionGoogleTutorialspoint
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Hint
Solution

Solution Hints

    
  
  • Use recursive approach for simplicity
    • 
  
  • Inorder: left subtree, current node, right subtree
    • 
  
  • Preorder: current node, left subtree, right subtree
    • 
  
  • Postorder: left subtree, right subtree, current node
    • 
  
  • Can be implemented iteratively using a stack for O(1) space complexity
    •

Steps to solve by this approach:

 Step 1: Implement inorder traversal (Left, Root, Right) using recursion.

 Step 2: Implement preorder traversal (Root, Left, Right) using recursion.

 Step 3: Implement postorder traversal (Left, Right, Root) using recursion.

 Step 4: For each traversal, visit left subtree, right subtree, and root in the appropriate order.

 Step 5: Collect visit results into separate lists for each traversal type.

 Step 6: Return all three traversal results.

Submitted Code :