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Lowest Common Ancestor of BST (Tree, Easy)

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Final answer:

The Lowest Common Ancestor in a BST is the lowest node that has two given nodes as descendants. To find the LCA, start from the root and traverse the tree based on the values of the nodes, which directs the search either left or right. An example is finding the LCA of nodes 3 and 10 in a BST with a root of 5.

Step-by-step explanation:

The question pertains to a concept within computer science related to data structures, specifically Binary Search Trees (BSTs). The Lowest Common Ancestor in a BST for two given nodes is the lowest node in the tree that has both nodes as descendants, where we define a node to be a descendant of itself according to the definition of LCA (Lowest Common Ancestor). To find the LCA of two nodes in a BST, we start at the root and traverse the tree. If both nodes are smaller than the root, we move to the left child. If both nodes are larger, we move to the right child. When the nodes are on opposite sides of a node, or we have reached one of the nodes, we have found the LCA.

An example can illustrate this: In a BST with nodes 3, 5, and 10, if you are looking for the LCA of nodes 3 and 10, you would start at the root. If the root node is 5, since one node is on its left and the other is on its right, the root is the LCA.

User Robert Wagstaff
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