Serialize and Deserialize Binary Tree: which companies ask it and how to practise

Serialize and Deserialize Binary Tree is a Hard problem that 22 companies are reported to ask. This page shows who, how often and how recently, what the question tests, and how to practise it out loud with an interviewer who asks follow-ups. We link to the original problem statement instead of copying it.

Which companies ask Serialize and Deserialize Binary Tree?

Public company lists attribute Serialize and Deserialize Binary Tree, a Hard problem, to 22 companies. The most frequent askers are Yahoo, Hive and Quora. 7 reports are from the last six months. It mainly tests string, tree and depth-first search. Use this as a practice guide, not a promise.

Practise this kind of question aloud

Who asks Serialize and Deserialize Binary Tree

22 companies appear in the public lists for this question. By how often each is reported: Yahoo (very often), Hive (very often), Quora (very often), Nutanix (often), Citadel (often), LinkedIn (often), Microsoft (often), TikTok (often), Uber (often) and Amazon (often), and 12 more. 7 of them were reported in the last six months, Quora, Microsoft and Uber among them.

These are candidate reports collected in public lists, not statements from the companies. They are a good guide to what to practise and a poor guide to what you will be asked: interviewers change questions, and the same company asks different questions by team and level. Last reviewed 25 October 2026.

What Serialize and Deserialize Binary Tree tests

It is rated Hard, so a correct brute force with a clear path to the better idea is a good result; interviewers watch how you reason when the answer is not obvious and how you use their hints.

String problems test careful index handling and knowing which characters you may assume. Say out loud whether the input is ASCII, whether case matters, and what an empty string should return.

Tree questions are usually a traversal with a small piece of state carried down or returned up. Say which one you chose.

Depth-first search follows one path to its end before backing up. Say how you mark visited nodes and what the recursion depth could be.

How to practise it

Do not just solve it silently. In a real interview you explain the approach before you code, write while you talk, and defend the solution to follow-ups. Set a timer, say the brute force and its cost first, then improve it, and finish by stating the time and space complexity and two edge cases you tested.

On giveinterview you can take this kind of question as a spoken interview: the AI interviewer opens with the problem, watches you code, asks cross-questions and ends with a scorecard. Your first 3 single-question interviews are free for life, every interview report is free, and a new account also gets 6 welcome credits.

Read the original statement here: https://leetcode.com/problems/serialize-and-deserialize-binary-tree/ (opens the publisher's page). The statement is theirs; we do not reproduce it.

Questions to practise next

If you can solve Serialize and Deserialize Binary Tree, try these next, chosen because they share its main topic and many of the same companies: Valid Parentheses (Easy), Longest Substring Without Repeating Characters (Medium), Group Anagrams (Medium), Longest Palindromic Substring (Medium), Longest Common Prefix (Easy) and Decode String (Medium). Each has its own page in the questions list.

Frequently asked questions

Is Serialize and Deserialize Binary Tree asked at Amazon?

Amazon appears in the public lists for Serialize and Deserialize Binary Tree, reported often. Treat that as a reason to practise it, not a promise you will be asked it.

How hard is Serialize and Deserialize Binary Tree?