Package g1001_1100.s1008_construct_binary_search_tree_from_preorder_traversal

Class Solution

java.lang.Object
g1001_1100.s1008_construct_binary_search_tree_from_preorder_traversal.Solution
public class Solution extends java.lang.Object
1008 - Construct Binary Search Tree from Preorder Traversal.

Medium

Given an array of integers preorder, which represents the preorder traversal of a BST (i.e., binary search tree ), construct the tree and return its root.

It is guaranteed that there is always possible to find a binary search tree with the given requirements for the given test cases.

A binary search tree is a binary tree where for every node, any descendant of Node.left has a value strictly less than Node.val, and any descendant of Node.right has a value strictly greater than Node.val.

A preorder traversal of a binary tree displays the value of the node first, then traverses Node.left, then traverses Node.right.

Example 1:

Input: preorder = [8,5,1,7,10,12]

Output: [8,5,10,1,7,null,12]

Example 2:

Input: preorder = [1,3]

Output: [1,null,3]

Constraints:

  • 1 <= preorder.length <= 100
  • 1 <= preorder[i] <= 1000
  • All the values of preorder are unique.

  • Constructor Summary

    Constructors
    Constructor
    Description
    Solution()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    TreeNode
    bstFromPreorder(int[] preorder)
     

    Methods inherited from class java.lang.Object

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

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • bstFromPreorder

      public TreeNode bstFromPreorder(int[] preorder)