Zig Zag Traversal (LeetCode 103) | Full Solution with visuals and a little trick | Study Algorithms

Actual Problem: leetcode.com/problems/binary-...
Chapters:
00:00 - Intro
00:47 - Problem Statement and Description
03:35 - Using level order traversal for zig-zag
08:54 - Dry-run of Code
13:38 - Final Thoughts
📚 Links to topics I talk about in the video:
Level Order Traversal: • Level order traversal ...
Stack Data Structure: • Stack Data Structure e...
Tree Data Structure: • Understanding Tree Dat...
📘 A text based explanation is available at: studyalgorithms.com
Code on Github: github.com/nikoo28/java-solut...
Test-cases on Github: github.com/nikoo28/java-solut...
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#leetcode #programming #interview

[@akshayrajsingh555]

Congratulations for 10k 🥳

[@LalitSingh-nd5vx]

thanks for awesome explanation !

[@susmitapatil4847]

Best Explanation. Keep doing good work.

[@tanishkaagarwal6750]

Thank you for the wonderful explanation sir

[@floatingfortress721]

Thanks! After watching this video I was able to solve a similar leetcode question, "Binary Tree Right Side View"

[@nikoo28]

that is wonderful

[@himanshisingh9]

loved the approach. writing how we made queue for level order and then thinking about how we can achieve zig zag pattern with small tweaks. thanks😇

[@nikoo28]

Glad you liked it.

[@deepondas5001]

sir i would say you have great approach and explanation skill if you have done a great marketing then you may have thousands of views

[@saurabhruikar1131]

As always very nice explanation, I would like to suggest a tweak instead of using stack we could simply reverse temporayList at alternate iteration.

[@nikoo28]

That's a great idea!

[@ghanashrim2839]

The way you approach a new problem is something I'd really like to learn. Amazing explanation as usual. What software do you use for video recording and editing? Is this iPad mirrored on the screen and then screen recorded?

[@nikoo28]

I use final cut pro for all the edits, and on iPad I use GoodNotes 5

[@ghanashrim2839]

@@nikoo28 Thank you :)

[@avinashtiwari4025]

can you also explain how we compute the space complexity for this ?

[@nikoo28]

space complexity is simply the extra space we use to arrive at our solution. We use a stack, that can have the maximum of n elements in the worst case. Hence, space complexity is O(n)

[@manishasharma-mh7fo]

sir could u pls make a video on boundary order traversal .

[@nikoo28]

can you give me an example link?

[@amitbhattacharya356]

There is a small mistake in the code while adding popped element from stack to level, which is self explanatory: Fixed code: TreeNode node = reverseStack.pop(); level.add(node.val); Appreciate your effort, thanks.

[@nikoo28]

Thanks for clearing it out. :)

[@saifahmad141]

which line??even the one on screen is running correct

[@mjeevan2408]

hi sir. I seen Ur backtracking video , I commented below that video can u replay for that comment.

[@nikoo28]

How can I help you?

[@navyashreeamam753]

@@nikoo28 I want more default problems with solutions on backtracking algorithm can u Make problems on that ,sir

[@vibhanshusharma9143]

Bro for instead of stack we can simply reverse a vector Batao m puch rha hu😅

[@pragyaprashar7165]

Hey Nikhil, I have messaged you on LinkedIn.