Subtree Weight Gap

For every node in a BST, define its 'Weight Gap' as the absolute difference between the sum of all node values in its left subtree and the sum of all node values in its right subtree. Find the value of the node that has the largest Weight Gap. If multiple nodes share the same maximum gap, return the node with the smallest value. Example: Input: 10 5 15 Node 5: LeftSum=0, RightSum=0, Gap=0 Node 15: LeftSum=0, RightSum=0, Gap=0 Node 10: LeftSum=5, RightSum=15, Gap=10 Largest gap is 10 at node 10. Output: 10

Key concepts

binary_search_treerecursionsubtree_analysis

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