Minimum Distance Between BST Nodes
A easy-tier problem at 60% community acceptance, tagged with Tree, Depth-First Search, Breadth-First Search. Reported in interviews at Wix and 0 others.
Minimum Distance Between BST Nodes is an easy problem that Wix has reportedly asked. You're given a binary search tree and need to find the smallest absolute difference between any two node values. The trap is overcomplicating it: most candidates try to compare every pair, which works but misses the elegant property that BSTs expose node values in sorted order during traversal. If you hit this problem cold in an online assessment and freeze on optimization, StealthCoder surfaces the in-order traversal insight instantly, invisible to the proctor. With a 60% acceptance rate, plenty of people get stuck on efficiency rather than correctness.
Companies that ask "Minimum Distance Between BST Nodes"
Minimum Distance Between BST Nodes is the kind of problem that decides whether you pass. StealthCoder reads the problem on screen and surfaces a working solution in under 2 seconds. Invisible to screen share. The proctor sees nothing. Built by a senior engineer who knows the OA is theater. This is the script.
Get StealthCoderThe key insight is that BST in-order traversal yields sorted values. Once you have them sorted, the minimum difference between any two nodes must occur between consecutive values in that sorted sequence. You can either collect all values during traversal then find the min difference, or track the previous node value on the fly to calculate differences in a single pass. Many candidates build a full comparison matrix or do multiple traversals unnecessarily. The problem tests whether you recognize the sorted property of BSTs and whether you can implement DFS cleanly. This is a straightforward application of Depth-First Search and Binary Search Tree knowledge. StealthCoder's value here is catching the moment you start writing O(n squared) logic and replacing it with the O(n) traversal pattern before you submit.
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Minimum Distance Between BST Nodes recycles across companies for a reason. It's easy-tier, and most candidates blank under the timer. StealthCoder is the hedge: an AI overlay invisible during screen share. It reads the problem and surfaces a working solution in under 2 seconds. Built by a senior engineer who knows the OA is theater. This is the script. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Minimum Distance Between BST Nodes interview FAQ
Is in-order traversal really the only efficient approach?+
Yes. Because a BST's in-order traversal is always sorted, the minimum difference must be between consecutive sorted values. Any other approach either repeats work or misses the fundamental property. Once you see it, it's immediate.
Do I need to store all node values, or can I track the previous one?+
You can track just the previous value as you traverse. This saves space and keeps the algorithm O(n) time and O(h) space, where h is height. Collecting all values first is simpler to code but uses more memory.
Does the tree structure (balanced vs. skewed) matter for the solution?+
No. The algorithm works regardless of balance because you're doing in-order traversal, which visits every node exactly once. Skew affects recursion depth, but not correctness or the core logic.
Why is this rated easy if so many people get stuck?+
The 60% acceptance rate suggests the problem is easy in theory but tricky in practice. Most failures come from not recognizing the sorted-order property or writing inefficient comparisons. Once you name the pattern, it's trivial.
How does this problem relate to other BST and DFS topics?+
It's a direct application of both. You need to understand how BST in-order traversal works and be comfortable with DFS recursion. It's a common warm-up before harder tree problems that require the same foundational skills.
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