Least Common Ancestor (LCA) problem.

You are given pointer to the root of the binary search tree and two values  and . You need to return the lowest common ancestor (LCA) of v1 and v2  in the binary search tree.

In the diagram above, the lowest common ancestor of the nodes 4 and 6 is the node 3 . Node 3  is the lowest node which has nodes 4  and 6 as descendants.


public static Node lca(Node root, int v1, int v2) {
if(root==null)return null;
Node curr=root;
if(curr.data > v1 && curr.data >v2){
else if(curr.data < v1 && curr.data <v2 ){
return curr;
return curr;

PROBLEM LINK : https://www.hackerrank.com/challenges/binary-search-tree-lowest-common-ancestor/problem

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