Leetcode 701. Insert into a Binary Search Tree

Input: root = [4,2,7,1,3], val = 5
Output: [4,2,7,1,3,5]
Explanation: Another accepted tree is:
Input: root = [40,20,60,10,30,50,70], val = 25
Output: [40,20,60,10,30,50,70,null,null,25]
Input: root = [4,2,7,1,3,null,null,null,null,null,null], val = 5
Output: [4,2,7,1,3,5]
  • The number of nodes in the tree will be in the range [0, 104].
  • -108 <= Node.val <= 108
  • All the values Node.val are unique.
  • -108 <= val <= 108
  • It’s guaranteed that val does not exist in the original BST.
  1. it’s a BST, if the value large than current node -> right side of tree; smaller than current node -> left side of tree
  2. create a current node to be a pointer, and return the root at the end of the answer



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Gary Chiang

Gary Chiang

CS new grad, 6 years experience related to supply chain management. Located in Bay area