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  "body": "\n## Summary\n\nIn graph theory and computer science, the **lowest common ancestor** (**LCA**) (also called **least common ancestor**) of two nodes $v$ and $w$ in a [[tree|062D9KXJB1]] or directed acyclic graph (DAG) $T$ is the lowest (i.e. deepest) node that has both $v$ and $w$ as descendants, where we define each node to be a descendant of itself (so if $v$ has a direct connection from $w$, $w$ is the lowest common ancestor).\n",
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