solve: lowest common ancestor of a binary search tree

Author: wogha95

lowest-common-ancestor-of-a-binary-search-tree/wogha95.js

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+/**
+ * TC: O(logN)
+ * left와 right 중 한 곳으로만 탐색
+ *
+ * SC: O(1)
+ */
+
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val) {
+ *     this.val = val;
+ *     this.left = this.right = null;
+ * }
+ */
+
+/**
+ * @param {TreeNode} root
+ * @param {TreeNode} p
+ * @param {TreeNode} q
+ * @return {TreeNode}
+ */
+var lowestCommonAncestor = function (root, p, q) {
+  while (root) {
+    if (root.val > p.val && root.val > q.val) {
+      root = root.left;
+    } else if (root.val < p.val && root.val < q.val) {
+      root = root.right;
+    } else {
+      return root;
+    }
+  }
+};