889. Construct Binary Tree from Preorder and Postorder Traversal

题目

Return any binary tree that matches the given preorder and postorder traversals.

Values in the traversalspre and postare distinctpositive integers.

Example 1:

Input: pre = [1,2,4,5,3,6,7], post = [4,5,2,6,7,3,1]
Output: [1,2,3,4,5,6,7]

Note:

1. 1 <= pre.length == post.length <= 30
2. pre[] and post[]are both permutations of 1, 2, ..., pre.length.
3. It is guaranteed an answer exists. If there exists multiple answers, you can return any of them.

解题思路

见程序注释