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Construct Binary Tree from Preorder and Inorder Traversal

MediumP2Coding

Given the preorder and inorder traversals of a binary tree with unique values, rebuild the tree and return its root.

Example 1

Input
preorder = [3,9,20,15,7], inorder = [9,3,15,20,7]
Output
[3,9,20,null,null,15,7]

Example 2

Input
preorder = [-1], inorder = [-1]
Output
[-1]

Constraints

  • 1 <= preorder.length <= 3000
  • inorder.length == preorder.length
  • -3000 <= values <= 3000
  • All values are unique and both arrays describe the same tree.

Hints

Run checks the 3 visible tests, Submit all 9.