Lowest Common Ancestor of a Binary Tree
Find the lowest common ancestor (LCA) of two nodes in a binary tree. The LCA is the lowest node that has both p and q as descendants.

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Lowest Common Ancestor of a Binary Tree
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Find the lowest common ancestor (LCA) of two nodes in a binary tree. The LCA is the lowest node that has both p and q as descendants.

Example 1:
Input: {"root":[3,5,1,6,2,0,8,null,null,7,4],"p":5,"q":1}
Output: 3
Constraints:

  • The number of nodes is in the range [2,105][2, 10^5].

  • −109≤Node.val≤109-10^9 \leq \text{Node.val} \leq 10^9

  • All Node.val are unique.

  • p != q

  • p and q will exist in the tree.

Input
arr ={"root":[3,5,1,6,2,0,8,null,null,7,4],"p":5,"q":1}

Finding LCA of nodes with values 5 and 1

Target (p/q)
Current Node
LCA Found
Visited
p
5
q
1
DFS Path

-

3

p

5

q

1

6

2

0

8

7

4

Variables
No variables to display
DepthFunction Call
Stack empty
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