Solution: Flatten Binary Tree to Linked List
Explore how to convert a binary tree into a linked list following preorder traversal using in-place depth-first search. This lesson teaches how to rearrange tree nodes by connecting subtrees efficiently without additional data structures, improving both time and space complexity while mastering tree transformations.
Statement
Given the root of a binary tree, the task is to flatten the tree into a linked list using the same TreeNode class. The left child pointer of each node in the linked list should always be NULL, and the right child pointer should point to the next node in the linked list. The nodes in the linked list should be in the same order as that of the preorder traversal of the given binary tree.
Constraints: