Binary Tree Algorithms for Technical Interviews - Full Course

Learn how to implement binary tree algorithms and how to use them to solve coding challenges. 🌳
✏️ This course was developed by Alvin Zablan from Structy. Check out Alvin's channel: / alvintheprogrammer
🔗 Learn data structures and algorithms: structy.net/
⭐️ Course Contents ⭐️
⌨️ (0:00:00) Course Introduction
⌨️ (0:01:09) What is a Binary Tree?
⌨️ (0:11:28) Binary Tree Node Class
⌨️ (0:14:19) Depth First Values - (structy.net/problems/depth-fi...)
⌨️ (0:36:00) Breadth First Values - (structy.net/problems/breadth-...)
⌨️ (0:47:43) Tree Includes - (structy.net/problems/tree-inc...)
⌨️ (1:05:35) Tree Sum - (structy.net/problems/tree-sum)
⌨️ (1:19:53) Tree Min Value - (structy.net/problems/tree-min...)
⌨️ (1:34:16) Max Root to Leaf Path Sum - (structy.net/problems/max-root...)
⌨️ (1:48:28) Conclusion
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[@davitkvaratskhelia4033]

I just watched day before to my interview and I was called today to be hired. Going to donate full of my first salary.

[@ytg6663]

Done ?

[@funnyvideo8677]

???

[@davitkvaratskhelia4033]

Sure, I’ve completed my sentence.

[@beqabeqa4955]

გამიხარდა ქართველის კომენტარი აქ და თან გამიკვირდა :დ

[@davitkvaratskhelia4033]

@@beqabeqa4955 ratom gagikvirda 😂

[@deniskhakimov]

This guy is the best! I just wanted to brush up on this topic and stumbled upon this precious lecture. Now I want to watch all his lessons 🤓👍

[@Secretzstolen]

I love that he goes over all the common mistakes people often make on the first try! It's very normalizing to see him show those mistakes, makes me feel much better lol, and also the explanations of those mistakes dig deeper and improve our understanding.

[@piglovesasy]

NOT confusing explanation, soothing and clear voice, so glad I found you! great work! thanks Alvin

[@omarshaikh1461]

Great video on Binary Trees. I was struggling to solve basic problems in Binary Trees and then i finally stumbled upon this video. The way Alvin walks through the course really drills down the concept in your head and makes you feel so comfortable ! Amazing 💯

[@muktarsayeed9198]

I like the way you broke down the recursion problems into base cases and general cases and tackled each one independently then combined it for the final solution. I think my issue was I tried to solve it in one go which led to me getting stuck. The recursive problems can be a real head wrecker if you're not careful!!

[@pammugaadu]

Thank you so much. It really helped me to understand the tree traversal in detail. Thanks again! I understood the DFS and BFS for the first time. Use of Queue and Stack for them is the key to understand the whole.

[@gagag96]

This was a great video and very well organized. I finished watching the whole video while coding the problems on Visual Studio Code in Python and now feel I have a good grasp of BFS, DFS, especially using recursion which I struggled with before. Thank you Alvin!

[@kowshikthopalli866]

did you code binary tree in python yourself? or is his code available in python somewhere ? TIA

[@madman3727]

@@kowshikthopalli866You can implement any code of any language once you have good grasp over the language you are learning

[@shaunakgalvankar4502]

Amazing videos alvin,got the clarity of thought needed for solving problems recursively and also dynamic programming doesn't seem a giant anymore

[@EsotericArnold]

ahh man , this is exciting to hear.

[@phen2841]

What a great course! For anyone wondering, I was able to follow along in Python despite the code being in JS with minimal issues! Would recommend

[@IldarSagdejev]

The recursive depth-first traversal is essentially the same as the solution using a stack, it's just that you're using the call stack as the stack for the algorithm.

[@carolfarris5967]

This course is so organized and clear! Outstanding work. Thanks for sharing these lessons on youtube!

[@mgkyawzayya4148]

Legend is coming back again.

[@soulju9144]

Alvin was born to teach anything coding related I'm certain. Got introduced to him while going through app academy and everytime i see a video of his I'll watch it several times over. Ofc I try to make an independent attempt at understanding but the amount of clarity that comes from him is amazing. Thank you

[@yuasufhelal7181]

Truly ❤

[@mdsiddic]

hey man you rocking, since 3 years i am learning data structure and algorithm.. i never feel this much understanding.

[@illogicalstuff6099]

I am still trying to figure out, how is he able to understand recursion so well, explain it so well, and master it so well. 🥺

[@matiasalarcon5061]

The topic was confusing for me and I really needed a some sort of direction to know where to start. I really appreciate this video, thank you very much man.

[@samihk1]

Covered this video in one night :D Amazing by the speed and quality of teaching from Alvin. Really helpful stuff, and recommend Alvin for getting prepared for DS&A.

[@bhargavpandya9189]

YES! Looking at the thumbnail emojis itself I knew I am gonna enjoy this video! Alvin is back!

[@riceball100]

This is an excellent video, when I sat down and really watched this thoroughly after practicing a bunch of binary tree algos, this helped to solidify even more concepts.

[@immythic8351]

Hi bro! I followed the whole video until the end and finally did the last exercise by my own and it worked! Thanks for the lessons , i love you and wish you a Merry Christmas ♥

[@user-mv3qi3xw6x]

it is incredible the way that you explain these challenging concepts with ease. I also watched your DP video and its amazing. Keep it going with the content

[@CauseOfFreedom-mc7fx]

Thanks Alvin for this and the dynamic programming course. They're both really helpful.

[@jrumac]

this is such a great video for quickly getting back up to speed on trees and basic tree traversal. thank you!

[@hmmm-ts3rb]

no way!!!! literally found his vids on dp and graphs last week, watching this asap.

[@BlueHat1]

This teach is the best! He really helps us visualize those abstract topics so well, which I'm sure helps a lot of people. Thank you!

[@khaino6828]

This guy is the best data structure and algorithm instructor I have known so far….

[@erikbustos2187]

Thank You a lot Alvin for the great Course. Definitively Structy is the best place to prepare efficiently for interviews.

[@dcts7526]

Loved that course, your teaching style is very clear and really easy to follow 💯🎉

[@milo_andrs]

Dude, the way you explain this is impecable. Great job, please keep making videos like this ✌️

[@zm690]

I really enjoy this tutorials, it is go step by step rather than throw all at once.

[@winniethepooh5509]

Thank you Programmer Alvin! Everything is very clear and easy to follow.

[@akhiltheloquacioussoul]

Omg! You just simplified things a lot for me. So easy to understand! Awesome video!

[@ajaypratapsingh240]

This is my second video of yours after linked list. Really appreciated you Bro.

[@luaneemiliano1041]

Amazing video! Thank you so much for sharing it with us. Keep up the great work.

[@pankajchaurasia14]

Thank you so much for all the efforts that you put through in getting this knowledge out for free. !

[@saurabhnambiar5514]

i am jus loving the fact that these are in Js ...Thankyou sir!

[@thilagavathiaruchamy2564]

Really appreciate this effort. Cant express in words how he explains clearly each concept.

[@dp2120]

Alvin is unbelievable. This is the best course on this topic. Impossible to do a better job.

[@Ziggy0120]

Alvin this is an excellent video. I wish you were my teacher when I started programming!

[@kydel10]

such a clear and helpful resource! you explain things so well!!!

[@benzz22126]

alvin is the best instructor on this channel. his voice and explanations are clear, and the animations help so much. thank you for this free education

[@Cdswjp]

looking forward to more videos; especially videos about optimized versions of algorithm solutions

[@dilichiokekearu1307]

This explanation helped me complete a major homework. Thank you.

[@mpalanipsbb]

One of the best tree algo videos on YT!

[@antoncid5044]

Your narration is great, thank you for the educontent

[@techtutorials5298]

This is some great content, so glad that I cam across this. Thank you for such clear tutorial

[@diniaadil6154]

For the last problem, you could consider the null nodes as your base case but return 0 rather than negative infinity. In that way they would not contribute to the path sum, and you won't have to add leaf nodes in your base case as both paths would return your current node value + 0. However, this only works knowing that the node values are positive.

[@rajbhandari9605]

Thanks! I was wondering the same thing.

[@tabancosmos2235]

I am here to review this and boy oh boy your teaching style is making me feel like a genius again. Well you are the genius. I feel the transfer of knowledge. I didn't even need to open my editor. Just pen an paper.

[@ignacioleikis1784]

Awesome course! Is there a way to print combinations / permutations using these binary trees? Is it also possible to construct composite trees (trees with nodes with more than two children)? Thank you!

[@radhikamanivannan6678]

I loved your Graph Algorithm. Could you please add more to it, more like an extension. Union find, problems like course schedule etc

[@lulusaikou221]

Thank you Alvin, now I'm a fan of recursion❤

[@qingxie8884]

Much appreciate! It´s very clear and easy to follow!

[@justdevi]

This guy is a legend, idek js but i coded it in python just by watching this video. Thank you so much for putting this gold out here for free

[@Dipenparmar12]

Thank you Alvin, That was an amazing tutorial on Binary tree so far.

[@iaaqibhussain]

Loved this course! Thank you for this.

[@AJ-rr5dv]

Alvin is the king!! Waiting for more videos form you!

[@anupampandey3758]

Hey @Alvin, is the time and space complexity of treeIncludes problem O(n) and O(logn) respectively for the recursive depth first

[@xiangluo1861]

Alvin is always very clear in his concepts

[@intcoder]

Great tutorial!! Thanks for the clear and detailed explanations!

[@Jmfufghf]

fantastic explanations. i would like some more information on when and where i would use these in the real world.

[@bhatanand]

You guys are simply the best. Thank you very much for these wonderful gems.

[@mehmetemin5404]

As usual, a great video from Alvin. Thanks

[@prudhvimanda7721]

beautifully explained. Thank you!

[@5uryaprakashp1]

@Alvin, you are best, your voice and the way you explained is just fabulous.

[@yogeshvasudevan]

Thank you Alvin. You are a great teacher.

[@supermanfan3805]

I don't comment much but man...your teaching skills are awesome. You explain like how a student want a teacher should explain to them.

[@kanzanaveed]

💯

[@siomarapantarotto]

Fantastic! I learned a lot with this tutorial. Thanks for sharing your knowledge with us. God bless you forever! ❤💯❤

[@deonvisser2480]

Nothing short of excellent. Thanks for this video!

[@shivamrastogi3154]

Hello, Why did the 3rd solution at 1:19:37 took less time to execute than the other two solutions?

[@filmbotreviews]

Great video! Really helped me improve my knowledge of trees.

[@benhardsim8629]

Alvin is my favorite tutor in free code camp, i always watch the video he make no matter what is it about. His video about dynamic programming and graph theory is really good , you guys should check it out. 👍

[@Jitendrakumar-gb7cn]

Yes he is very good , have you seen his dp tutorial?

[@Sz-hi7wj]

@@Jitendrakumar-gb7cn ,, His video about dynamic programming and graph theory is really good"

[@Andboldquates]

i've learned lot about binary tree even half of the video , thanks lot

[@natali_li90]

Thank you for this amazing course!

[@snoudoubts1745]

I’m in awe of how good this guy is in every video.

[@akshaychavan5511]

Alvin is right. It's tricky to implement BFS using recurision and I did implement it - def BFS_recursive(root: Node): def myBFS(root:Node): if not root: return [] result = [] if root.left: result.append(root.left.val) if root.right: result.append(root.right.val) leftValues = myBFS(root.left) # [d,e] rightValues = myBFS(root.right) # [f] result+=(leftValues+rightValues) return result return [root.val]+myBFS(root) print('Recursive BFS output as list =>') print(BFS_recursive(a))

[@GabrielFermy]

This is a very greate tutorial and explaination. This video describe how a programmer mind set should be when facing problems in step by step.

[@elenakusevska6266]

Great explanations ! It took me less than 5 mins to implement each :)

[@harshrajput3547]

Even before starting the video, I knew it's gonna be Alvin

[@calebtaylor2487]

At 33:47 I’m not sure why his recursive version doesn’t return the empty [] into the right side values array when it assess that C has no left hand value. Shouldn’t there be an empty array present in the result?

[@prateekgoyal2703]

amazing explanation! Thank you so much!!

[@jayrollo1352]

Alvin is the best teacher dude.

[@KrisMeister]

The shift operation runs in O(n) time. Why is your breadth first example running in O(n) instead of O(n^2) ?

[@aidardusukov2263]

Thank you so much! It was really helpful!

[@MadHolms]

to complicate the things, for the Max sum of paths, I'd like to also get the actual node values in an array. How would I do this?

[@itsmohitkhudotiya]

not sure how leftvalues constant is returning an array at 35:01 Could someone please explain?

[@tabhashim3887]

For the last problem (Max Root to Leaf Path Sum) I feel like writing it this way is a bit more elegant but also makes a bit more sense to me, in case it helps anyone: def max_r2l_R(root): if(root==None): return 0 return max( root.val+max_r2l_R(root.left), root.val+max_r2l_R(root.right) ) This has ONLY 1 base case, because if you are at a leaf node, When you recursively call the function on the children you will hit the base case, which will return 0, effectively not altering your sum. This is Python, but the idea should still hold :)

[@tugayersoy4489]

this video was amazing, ty for effort

[@tonyiommisg]

What is my base case for finding minimum value in a tree when doing this in python. It feels wrong to just use infinity?

[@forexsanjose6090]

The depth first traverse with stack seems to work the same with preorder iteration?

[@CodewithRSV]

These are some premium quality tutorials.

[@suar_pilla]

Can some one tell me what kind of traversal is being shown here when explaining the DFS? Is it InOrder,Pre or PostOrder?

[@haykisayan2206]

A perfect video. Instantly subscribed!

[@jorgebautista171]

Great video, as always.

[@MukeshSharma-xd4dn]

Super cool video, Thanks

[@thongphan4277]

Thanks for a concise lecture on Binary Tree

[@user-qh5qo2tr7l]

Thank you very much. It was very thoughtful, interesting and useful video

[@InnocentZvovuranda]

Love this guy, keep on doing this

[@VitaminBeast3]

Wow, this even helped me in my lumberjack career

[@wolffcaleb1]

😂 A+

[@Gs0c]

Wow this is amazing. Thank you so much!