Given a binary search tree (BST), find the lowest common ancestor (LCA) of two given nodes in the BST.
\n\nAccording to the definition of LCA on Wikipedia: “The lowest common ancestor is defined between two nodes p and q as the lowest node in T that has both p and q as descendants (where we allow a node to be a descendant of itself).”
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Example 1:
\n![\"\"](\"https://assets.leetcode.com/uploads/2018/12/14/binarysearchtree_improved.png\")
\n\nInput: root = [6,2,8,0,4,7,9,null,null,3,5], p = 2, q = 8\nOutput: 6\nExplanation: The LCA of nodes 2 and 8 is 6.\n\n\n
Example 2:
\n\n\nInput: root = [6,2,8,0,4,7,9,null,null,3,5], p = 2, q = 4\nOutput: 2\nExplanation: The LCA of nodes 2 and 4 is 2, since a node can be a descendant of itself according to the LCA definition.\n\n\n
Example 3:
\n\n\nInput: root = [2,1], p = 2, q = 1\nOutput: 2\n\n\n
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Constraints:
\n\n[2, 105].-109 <= Node.val <= 109Node.val are unique.p != qp and q will exist in the BST.Compiled with clang 11 using the latest C++ 17 standard.
Your code is compiled with level two optimization (-O2). AddressSanitizer is also enabled to help detect out-of-bounds and use-after-free bugs.
Most standard library headers are already included automatically for your convenience.
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