Construct Binary Tree from Preorder and Inorder Traversal
Given the preorder and inorder serialization of a binary tree, construct a tree data structure. Tags: Recursion, Search, Trees
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# Definition for a binary tree node.
# class TreeNode:
# def __init__(self, val=0, left=None, right=None):
# self.val = val
# self.left = left
# self.right = right
class Solution:
def buildTree(self, preorder: List[int], inorder: List[int]) -> TreeNode:
if not inorder:
return None
root = preorder.pop(0)
idx = inorder.index(root)
node = TreeNode(root)
node.left = self.buildTree(preorder, inorder[:idx])
node.right = self.buildTree(preorder, inorder[idx + 1:])
return node