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Md Ariful Haque @mah-shamim

Recover Binary Tree From Preorder Traversal In 60 Characters

Recover binary tree from preorder traversal string: parse dashes for depth & build tree with stack-based approach, ensuring left children are prioritized.

1028. Recover a Tree From Preorder Traversal
Difficulty: Hard
Topics: String, Tree, Depth-First Search, Binary Tree
We run a preorder depth-first search (DFS) on the root of a binary tree.
At each node in this traversal, we output D dashes (where D is the depth of this node), then we output the value of this node.  If the depth of a node is D, the depth of its immediate child is D + 1.  The depth of the root node is 0.
If a node has only one child, that child is guaranteed to be the left child.
Given the output traversal of this traversal, recover the tree and return its root.
Example 1:


Inp...