Completed Trees-1

[ManasviReddy25]

No description provided.

[super30admin]

Validate Binary Search Tree (Problem1.py)

Strengths:

• Clear and well-commented code that explains the in-order traversal approach
• Proper use of self. prefix for instance variables
• Good variable naming (prev, flag, currentNode)
• Correct handling of edge cases (None nodes, first node comparison)
• The comment at the top explaining the approach is excellent

Areas for Improvement:

• Consider adding an early return when flag becomes False to avoid unnecessary recursive calls (minor optimization)
• Could add type hints for better code documentation (e.g., def isValidBST(self, root: Optional[TreeNode]) -> bool: is already present, which is good)

The solution is functionally equivalent to the reference solution and demonstrates good understanding of the BST validation problem using in-order traversal.

VERDICT: PASS

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Construct Binary Tree from Preorder and Inorder Traversal (Problem2.py)

Strengths:

• Clear and comprehensive comments explaining the approach
• Good use of descriptive variable names
• Efficient use of dictionary for O(1) index lookups
• Correct recursive structure with proper base case
• Well-documented time and space complexity analysis

Areas for improvement:

• The solution is already well-optimized; no significant improvements needed
• Could consider adding type hints for better code documentation (e.g., preorder: List[int])
• The import statement for List and Optional types is missing from the code snippet

The solution demonstrates a solid understanding of the problem and implements an efficient, correct algorithm.

VERDICT: PASS