1123. Lowest Common Ancestor of Deepest Leaves
https://leetcode.com/problems/lowest-common-ancestor-of-deepest-leaves
Description
Given the root
of a binary tree, return the lowest common ancestor of its deepest leaves.
Recall that:
The node of a binary tree is a leaf if and only if it has no children
The depth of the root of the tree is
0
. if the depth of a node isd
, the depth of each of its children isd + 1
.The lowest common ancestor of a set
S
of nodes, is the nodeA
with the largest depth such that every node inS
is in the subtree with rootA
.
Note: This question is the same as 865: https://leetcode.com/problems/smallest-subtree-with-all-the-deepest-nodes/
Example 1:

**Input:** root = [3,5,1,6,2,0,8,null,null,7,4]
**Output:** [2,7,4]
**Explanation:** We return the node with value 2, colored in yellow in the diagram.
The nodes coloured in blue are the deepest leaf-nodes of the tree.
Note that nodes 6, 0, and 8 are also leaf nodes, but the depth of them is 2, but the depth of nodes 7 and 4 is 3.
Example 2:
**Input:** root = [1]
**Output:** [1]
**Explanation:** The root is the deepest node in the tree, and it's the lca of itself.
Example 3:
**Input:** root = [0,1,3,null,2]
**Output:** [2]
**Explanation:** The deepest leaf node in the tree is 2, the lca of one node is itself.
Constraints:
The number of nodes in the tree will be in the range
[1, 1000]
.0 <= Node.val <= 1000
The values of the nodes in the tree are unique.
ac
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