LeetCode : 235. Lowest Common Ancestor of a Binary Search Tree

문제

Given a binary search tree (BST), find the lowest common ancestor (LCA) node of two given nodes in the BST.

According 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).”

Constraints:

• The number of nodes in the tree is in the range [2, 105].
• 109 <= Node.val <= 109
• All Node.val are unique.
• p != q
• p and q will exist in the BST.

 

풀이

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