# Lowest common ancestor of a Binary Tree

Lowest common ancestor between two nodes n1 and n2 is defined as the lowest node in the tree that has both n1 and n2 as descendants.

# Finding lowest common ancestor

Consider the tree:

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Lowest common ancestor of nodes with value 1 and 4 is 2

Lowest common ancestor of nodes with value 1 and 5 is 3

Lowest common ancestor of nodes with value 2 and 4 is 4

Lowest common ancestor of nodes with value 1 and 2 is 2