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 Summary

Constructors

Constructor and Description
Solution()

Method Summary

Modifier and Type	Method and Description
TreeNode	constructFromPrePost(int[] preorder, int[] postorder)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Solution

public Solution()

Method Detail

constructFromPrePost

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