Package g0801_0900.s0889_construct_binary_tree_from_preorder_and_postorder_traversal

Class Solution

java.lang.Object
g0801_0900.s0889_construct_binary_tree_from_preorder_and_postorder_traversal.Solution
public class Solution extends Object
889 - Construct Binary Tree from Preorder and Postorder Traversal.

Medium

Given two integer arrays, preorder and postorder where preorder is the preorder traversal of a binary tree of distinct values and postorder is the postorder traversal of the same tree, reconstruct and return the binary tree.

If there exist multiple answers, you can return any of them.

Example 1:

Input: preorder = [1,2,4,5,3,6,7], postorder = [4,5,2,6,7,3,1]

Output: [1,2,3,4,5,6,7]

Example 2:

Input: preorder = [1], postorder = [1]

Output: [1]

Constraints:

  • 1 <= preorder.length <= 30
  • 1 <= preorder[i] <= preorder.length
  • All the values of preorder are unique.
  • postorder.length == preorder.length
  • 1 <= postorder[i] <= postorder.length
  • All the values of postorder are unique.
  • It is guaranteed that preorder and postorder are the preorder traversal and postorder traversal of the same binary tree.

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • constructFromPrePost

      public TreeNode constructFromPrePost(int[] preorder, int[] postorder)