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What approach will you follow to find the lowest common ancestor LCA of any two nodes in BST?
Recursive Approach. The lowest common ancestor for the two nodes node1 and node2 would be the last ancestor node common to both of them.
Is a parent an ancestor?
An ancestor, also known as a forefather, fore-elder or a forebear, is a parent or (recursively) the parent of an antecedent (i.e., a grandparent, great-grandparent, great-great-grandparent and so forth). Ancestor is “any person from whom one is descended. In law, the person from whom an estate has been inherited.”
Is my dad my ancestor?
How to find the lowest common ancestor in a binary tree?
Given a binary tree, find the lowest common ancestor (LCA) of two given nodes in the tree. 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 ).”
How to find LCA of a binary tree?
The following are different approaches to find LCA in Binary Tree. Following is a simple O (n) algorithm to find LCA of n1 and n2. 1) Find a path from the root to n1 and store it in a vector or array. 2) Find a path from the root to n2 and store it in another vector or array. 3) Traverse both paths till the values in arrays are the same.
Which is the lowest common ancestor between N1 and N2?
The lowest common ancestor between two nodes n1 and n2 is defined as the lowest node in T that has both n1 and n2 as descendants (where we allow a node to be a descendant of itself). The LCA of n1 and n2 in T is the shared ancestor of n1 and n2 that is located farthest from the root.
How to find the LCA of a node?
If any such node is present in the tree, then it is LCA; if y lies in the subtree rooted at node x, then x is the LCA; otherwise, if x lies in the subtree rooted at node y, then y is the LCA. The algorithm can be implemented as follows in C++, Java, and Python: // both `x` and `y` are present in a binary tree.