98. Validate Binary Search Tree

LeetCodeTreeDepth-First SearchBinary Search TreeBinary TreeOpen on judge ↗

Given the root of a binary tree, determine if it is a valid binary search tree (BST). A valid BST is defined as follows: - The left subtree of a node contains only nodes with keys strictly less than the node's key. - The right subtree of a node contains only nodes with keys strictly greater than the node's key. - Both the left and right subtrees must also be binary search trees. Example 1:

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solution.cppC++17

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