Linked Lists for Technical Interviews - Full Course

[@Historyiswatching]

I've watched sooooooooo many KZbin tutorials - this guy is legit the best teacher I've come across so far! Very clear. Thank you so much Alvin

[@ragsbigfella]

I love Alvin's way of teaching. I loved his Dynamic programming video. Please ask him to make some more videos like Graphs and Trees.

[@spaceface2288]

He already made videos on those topics bruh

[@veganaiZe]

Graphs: kzbin.info/www/bejne/aJC4ppyuqchon5I

[@calebo.a.6270]

Same here

[@mehulsolanki9435]

@@spaceface2288 He's going to love them.

[@maozbenkalif598]

08:25 one small correction, the order of inserting a node to a linkedlist is that the node you wish to enter has to point first to the node and then you have to take node b to point on node q, if you start by pointing b to q first you will lose all the data of c and d. Great video !! loved it

[@ehabahmedyassen]

yup, q.next = c then b.next = q

[@m.y.7230]

Hands down the best explanation for linked list. It finally clicked on me after 3 days banging my head against the wall. His algorithms are way more intuitive, both iterative and recursive versions, much much more than what other instructors talked about. Thank you!

[@EnriqueMoranG]

Bro you explain so good that i've been able to perform the tasks without watching the whole video. Just got the idea and solved it by myself. I love you, Alvin. Happy New Year, mate!

[@aliqyan9827]

same!

[@Jamesxoxo89]

Started learning linked list this week and could not understand the code for it at all until this video... Super appreciative, this community exists.

[@chukwunta]

This is all you need to learn about linked-list. This is my fifth time viewing and I always seem to comeback and learn something new. It is such an amazing resource. Thanks @Alvin

[@morenomt27]

Thank you for this Alvin. I had a hard time refreshing linked list by watching countless tutorials and I can't understand why I can't move on with problems. While you are explaining, I am able to answer problems!

[@AshenafiGodana-m1u]

This is the only programming video I watched from start to finish with one sitting and I clearly understood LinkedList. Thank you Alvin!

[@zeynepdagci1]

your courses're amazing!! I have an interview with google in a couple of hour, I hope your courses work for me !!!

[@fastdesigns8895]

did they

[@tf1n]

Best video on LL’s that I’ve seen. Thank you, Teacher Alvin!

[@abolfazljahangir1651]

You are amazing Alvin! I've learned a lot from you🙌

[@sriram-uu6yd]

Trust me, I was searching for an hour yesterday to find a good resource to learn Linked Lists. Thank you, FCC.

[@AnkurSharma-hf9jn]

Best explanation ever Now I'm much more confidence writing link list problem.

[@RahulD600]

I love Alvin's way of teaching! He's really a master! Thank you very much!

[@Pupu._]

Alvin is so to the point and voice is good to hear 🙌

[@talios6824]

Absolutely the best tutorial video on linked lists. Thank you so much, Alvin! Fantastic teacher.

[@skitzhills]

Alvin you are the best programming sensei. This Linked List tutorial is just ridiculously good...

[@pankkajsen]

Given a blind like because of Alvin👍…and added to my “Immediate watch” list 😀

[@Luke-gr6dg]

I love that you said "A"'s next is "B". That makes link list much easier to conceptualize than other sources which overly complicate it.

[@whetfaartz6685]

That's exactly how I see it

[@zeganikhalid9730]

man this is the best explanation ever.

[@tonyseben]

For the iterative Zipper implementation, we need a null check for head1 (ideally for head2 as well). if(head1 === null) return head2; if(head2 === null) return head1;

[@a_maxed_out_handle_of_30_chars]

seeing alvin puts a smile on my face :)

[@freecodecamp]

Same.

[@omarkyon1933]

Really cool to see you here Alvin. Great explanations as usual

[@myrusEW]

I just realized watching theory tutorials in other languages actually makes learning so much more intuitive, since you can't just blindly copy. You're forced to understand how your language works, and you're forced to implement those ideas without really being able to "cheat". Wow. I'm gonna start watching C tutorials and do them in python. I'm about to hit 10x developer once I understand all this

[@servantofthelord8147]

This is a very good point. I never realized this. This whole time I was trying to avoid tutorials in different languages, not realizing that they were the key to helping my solidify my understanding. Good observation!

[@madman3727]

same I was forced to code this in my learning language and I was surprised to see how quickly I learned

[@ArudSekaBerneLearnings]

I love the way he explain and able to grasp things even though I am a beginner.

[@sanjaypaudel3296]

Alvin we need more of you guys. Grow up your channel. You are a hero

[@foravidalalsharma1291]

I wish you had Java as one of the programming languages, but I still loved your course and was able to interpret everything in Java because of how you explained the algorithms, it was so simple to even understand recursive, something I always mess up. Thank you!!

[@michaels7159]

No

[@av12-db]

Your videos are awesome..Saw your video on Dynamic programming and since then i am not facing any problem in solving such questions.

[@madhubalajayakumaran9340]

loved the explanation! Though I knew all these concepts before, I just watched anyway.

[@pauzhou8639]

omg who is this guy? He has the best algor interview videos !!

[@andiuptown1711]

Alvin! Ex Google engineer. He also put out a new React + Tailwind course

[@doctype7430]

I like the way Alwin simplifies the concepts and problems. learnt a lot. Thanks

[@shyamprakashm6325]

What a co-incidence .tomorrow we have a amazon technical interview , hope It would help.

[@sampathsai5509]

I love the way you teach 😍. Please create a course on Backtracking.

[@thelastminutetrade]

Bro your research and best way of analysis is amazing. Who else find this list helpful ❣️❣️

[@sculptscript]

9:07 Linked list insertion at an index which is not at the head or the tail should be O(k) Time right?

[@Jutastre]

Yup, and because you're hopping through so many pointers, you get a lot more cache misses than an array, more often than not making it slower than an array in practice.

[@vaibhavpathak786]

Thanks!

[@CHITUS]

Bro your research and best way of analysis is amazing. Who else find this list helpful ️️

[@andr3w321]

@1:21:40 Unless I'm missing an edge case, there's no need for the count variable in the iterative zigzag solution. Just move tail twice in each while loop. C++ code below Node* zigzag3(Node* head1, Node* head2) { Node* tail = head1; Node* cur1 = head1->next; Node* cur2 = head2; while(cur1 && cur2) { tail->next = cur2; cur2 = cur2->next; tail = tail->next; tail->next = cur1; cur1 = cur1->next; tail = tail->next; } if (cur1) tail->next = cur1; if (cur2) tail->next = cur2; return head1; }

[@sufalt123]

this was my solution: template Node* zipper(Node* head1, Node*head2) { auto current1 = head1; auto current2= head2; while(current1 != nullptr && current2 != nullptr) { auto next1 = current1->next; auto next2 = current2->next; current1->next = current2; current2->next = next1==nullptr?next2:next1; current1=next1; current2 = next2; } return head1; }

[@michaelkofron3994]

Why at 30:53 does he create a new function for the recursive version? Why is he afraid of creating multiple arrays when JS arrays are pass by reference?

[@eshw23]

Amazing, this guy is dynamic and engaging

[@Guru_Bloke]

Thanks. This is top notch. On my way to subscribe. Frankly best content ever. Quick and eloquent.

[@gautamgunecha5963]

His tutorial are pure 💎

[@sane7263]

I think it's much elegent this way. Anyway it was superb tutorial, Thanks Alwin! node *ZippedLL(node *A, node *B){ if(!A) return B; if(!B) return A; node *ptrA = A; node *ptrB = B; while(ptrA && ptrB){ node *nextA = ptrA->next; node *nextB = ptrB->next; if(ptrB) ptrA->next = ptrB; if(nextA) ptrB->next = nextA; ptrA = nextA; ptrB = nextB; } return A; }

[@nonconsensualopinion]

At least one error you will get is that you will be stuck in a loop. ptrA and ptrB are pointers and not booleans. Their values will likely be non-zero which will be interpreted as true. You need " While (ptrA != nullptr &&...) ". Something like that. Here is my code which I think works how you intended. /// Assumes that neither list is empty. void * zip(Node* f, Node* s){ while(f != nullptr && s != nullptr){ // Save next pointer. Node* n = f->next; // Point element from this list to other list. f->next = s; // Update first and second node. f = s; s = n; } }

[@sane7263]

@@nonconsensualopinion it works the way it is intended, NULL will be treated as false. Your code it correct, but I am not quite sure where am' wrong

[@andreytsapko4213]

Best explanation of LinkedList ❤

[@tomashoracek7187]

Awesome vids helping me with my uni subject Foundations of Programming, they give us 15 small programming exercises every week for points that count to final mark and also credit and they gave us exercises such as programm ringbuffer using linked list, program queues and stack using linked list. Merge two ordered linked lists and so on xd

[@Sz-hi7wj]

welcome back Alvin!

[@rashidselemani475]

The way you explain the link list, even a foolish can understand it. Thanks a lot 😊

[@eda-un8zr]

Awesome. Alvin is a great teacher

[@stanleyjekwu6810]

The best I have seen so far...Thank you so much... I just checked your platform to make a purchase to go deeper but I couldn't find C# language option (that's my core language). I don't know if there will be room for that in the future? I greatly benefited from this JavaScript version.

[@nathanexclusive9261]

The way Alvin teaches linked lists makes these concepts NOde big deal. Haaa

[@japarjarkynbyek8494]

Love it as always! Big kudos!

[@saplay3372]

All the members of your department are great

[@heybibleefan]

BEST LINKEDLIST VIDEO EVER

[@alexbolych2366]

Thank you very much. The best explanaition of js linked lists

[@sandeepchandupatla7832]

Completed watching this tutorial, very informative, thanks a lot 🎉😊

[@johnnyf1624]

i rlly like the way you explain the problem step by step.

[@bruhmoment3731]

what an excellent teacher!

[@iamlookto]

Realy nice teaching style. Just one question. @ 37:00 it says the space is O(n) for the recursive sumList function. That is true for how it is implemented. But couldn't we also achieve O(1) by passing the sum variable into every recursion like it's done with the recursive linkedListValues? Wouldn't hat be much more optimised?

[@atharvarane6165]

From what I understand, space complexity of O(n) means, in the worst case there will be 'n' call stacks ( i.e when we reach the tail of the linklist), thus passing the integer as a argument will still create n call stacks, hence O(n).

[@iamlookto]

@@atharvarane6165 then why is it different in the recursive version of linkedListValues?

[@atharvarane6165]

@@iamlookto Must be a mistake, because the memory complexity is determined by the number of return statements because each function call will be stored on the program stack. To generalize, a recursive function's memory complexity is O(recursion depth). As our tree depth suggests, we will have n total return statements and thus the memory complexity is O(n).

[@kuxnal]

The video that I had been searching. Thank you so much

[@saurabhnambiar5514]

The Dynammic programming one was a blockbuster hence m here cheer

[@rebeccaburch3334]

for zipperlist iterative approach, when you add the rest of the list that is leftover tail isn't reassigned to be the new tail. In this case, you're just using "tail" as a pointer to the current end of the constructed list. And tail isnt assigned at all in the recursive solution. Would there be an extra step to iterate through the leftover list to the end and reassign tail? Thanks for your great videos 🔥🔥🔥

[@georgeimus6102]

not gonne lie thought this video was gonna be a waste of my time but I learned linked lists in just the first 15 mins of the video and was able to swift by these easily.

[@kamaboko1]

Hands down the best algorithm explanations. $ Structy purchase.

[@ahmedhamdytube]

Alvin you are a great teacher.

[@DrewOsmond]

Great video Alvin!

[@hi-tk4hu]

Best video on LL for beginner

[@sufalt123]

kinda cool that i found different (tho worse) solutions to some of the problems on my own :D

[@kehinde10100]

Best teacher ever!!!

[@mishkathossain2984]

Alvin the boss is back in the hood!!!!!!

[@abdulwakilabdulkadir8288]

My comment may not matter much, but this video is amazing. I have to say

[@sharangkulkarni1759]

last zipper recursion was awesome beauty

[@PrashantNigam]

My dude is back!!!

[@jimmykitty]

As Always, Thanks a Trillion..... ♥️♥️♥️♥️♥️♥️♥️♥️🌿🌿🌿🌿🌿🌿

[@ayushmishra6740]

Smooth Explanation.

[@dev-skills]

19:15: great advice not to premature checking on linked list

[@intcoder]

Awesome Video!!! thanks for the detail explanations.

[@eidmone8684]

ALVIN the GOAT!

[@gunratnamore]

Helpful always 👍

[@mrrishiraj88]

True

[@ankit-h8470]

@@mrrishiraj88 This_Reply = True;

[@TheManBehindTheScen1]

My Recursive Solution for Zipper List is MORE concise and easier to learn: const zipperLinkedListRec = (head1, head2) => { if (!head2) return; let temp = head1.next; head1.next = head2; zipperLinkedListRec(head2, temp); return head1; }; *This assumes that both lists are non-empty like in video

[@sufalt123]

cooooooooool

[@AlThePal78]

this is literally the best video I seen on this. However, you said it can be anything in the data. However, in C# and Java would be different. it would have to be what you choose it to be because you have to initialize the type of data it has to enter so all the nodes would have integers. Am I right or am I wrong?

[@dzni9061]

you have saved my life

[@vishaloza6981]

thank you! needed this video!

[@johnbright8172]

Thank you so much. You're the best!!!!

[@ehabahmedyassen]

I solved ZipperList iteratively without a counter to toggle between the two lists because at the start, i position the tail at the end of the initially constructed zipped list then within the while loop i construct the next node as a linkedlist of two nodes (current1.val) -> (current2.val) and then i update the tail and set the constructed two-nodes-list as its next then i refer to the last node of two-nodes-list i have just added as the new tail. private static Node zipListsIterative(Node head1, Node head2) { Node zipped = new Node(head1.getVal(), new Node(head2.getVal())); Node tail = zipped.getNext(); Node current1 = head1.getNext(); Node current2 = head2.getNext(); while (current1 != null && current2 != null) { Node next = new Node(current1.getVal(), new Node(current2.getVal())); tail.setNext(next); tail = next.getNext(); current1 = current1.getNext(); current2 = current2.getNext(); } if (current1 == null) tail.setNext(current2); if (current2 == null) tail.setNext(current1); return zipped; } and recursively, i wrote the recursive case as one liner by making use of the constructor: Node(String val, Node next) private static Node zipListsRecursive(Node head1, Node head2) { //base cases if (head1 == null && head2 == null) return null; if (head1 == null) return head2; if (head2 == null) return head1; //recursive case return new Node(head1.getVal(), new Node(head2.getVal(), zipListsRecursive(head1.getNext(), head2.getNext()))); }

[@havefun5519]

Thanks man, your recursive method is great

[@havefun5519]

2nd watched.

[@havefun5519]

Last zipper recursive method is not easily to understand.

[@alexroy4235]

Excellent explanation

[@rem.kudusov]

Thank you, bro!

[@monadastar9393]

great help! thank you

[@Singh54321]

learned trees now this thanks man

[@banjohead66]

I believe that it was David Seville who so famously said ALVIN!

[@mohamedtaherali8914]

i think insertion in time complexity is O(n) in worst case this is most significant for linked list because we cant reach index till we reach the previous one and so on .. that's right ?

[@LongDistance22]

You teach better than majority of my professors. Why couldnt you be my professor? Why am i stuck with spoiled professors that have no passion for teaching and explain bad

[@orangekitty5192]

Great teacher!

[@teodora_cassualo]

best teacher :DD

[@79Nardo]

Excellent!

[@parmachine470]

Do you just use a wrapper function in your course when you have visited or memo?

[@sohamali7018]

Thankyou Very Very Much🙂🙂🙂🙂🙂🙂

[@sergiocayuqueov]

Good job.

[@gopalks6437]

Amazing !