Is Minimum Distance Between BST Nodes easy or hard?

Minimum Distance Between BST Nodes is classified as an Easy problem. The main insight is recognizing that inorder traversal of a BST produces sorted values, allowing the minimum difference to be found by comparing adjacent nodes during a single traversal.

Minimum Distance Between BST Nodes Python/Java solution

Python and Java implementations typically perform recursive inorder traversal while tracking a previous node value and the current minimum difference. The logic remains identical across languages: traverse left, process node, update difference, then traverse right. Time complexity stays O(n).

How to solve Minimum Distance Between BST Nodes in O(n)?

Perform an inorder traversal of the BST to process node values in sorted order. Maintain a variable storing the previous node value and compute the difference with the current node. Update the minimum difference each time you visit a node. Since each node is visited once, the algorithm runs in O(n) time.

What is the best approach for Minimum Distance Between BST Nodes?

The best approach uses inorder traversal of the Binary Search Tree. Since inorder traversal produces values in sorted order, the minimum difference must appear between two consecutive nodes in that sequence. Track the previous visited value and update the minimum difference during traversal. This runs in O(n) time with O(h) stack space.

Is Minimum Distance Between BST Nodes asked at Google/Amazon/Meta?

BST traversal problems frequently appear in interviews at companies like Amazon, Google, and Meta. Variants often ask for minimum difference, kth smallest element, or validating BST properties. This problem tests understanding of inorder traversal and the sorted nature of BST nodes.

What data structure is used in Minimum Distance Between BST Nodes?

The problem uses a Binary Search Tree. The algorithm relies on depth‑first traversal (inorder DFS) to process nodes in sorted order. Some implementations also use a stack for iterative traversal or Morris traversal for constant-space processing.

What is the time complexity of Minimum Distance Between BST Nodes?

The optimal time complexity is O(n) because every node in the BST is visited exactly once during traversal. Space complexity is O(h) for recursive inorder traversal where h is the tree height, or O(1) when using Morris traversal that avoids recursion and extra stacks.

Description Solution Video 8:01

783. Minimum Distance Between BST Nodes

Easy61.8% acceptance4 companies

Given the root of a Binary Search Tree (BST), return the minimum difference between the values of any two different nodes in the tree.

Example 1:

Input: root = [4,2,6,1,3]
Output: 1

Example 2:

Input: root = [1,0,48,null,null,12,49]
Output: 1

Constraints:

The number of nodes in the tree is in the range [2, 100].
0 <= Node.val <= 10⁵

Note: This question is the same as 530: https://leetcode.com/problems/minimum-absolute-difference-in-bst/

Asked at 4 companies

Wix

Google Amazon Meta

Topics

8:01

Still stuck?Read 3 approaches, or watch a walkthrough.

Open solution

783. Minimum Distance Between BST Nodes

Asked at 4 companies

Topics

Similar problems