Implement Queue using Stacks - Leetcode 232 - Python

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Problem Link: leetcode.com/problems/impleme...
0:00 - Read the problem
0:36 - Drawing Explanation
12:11 - Coding Explanation
leetcode 232
#neetcode #leetcode #python

Пікірлер: 35

  • @NeetCodeIO
    @NeetCodeIO5 ай бұрын

    Even though this is an easy, I spent some extra time to really explain why the solution works. I think it's tricky enough to warrant that, but let me know if it felt too long though.

  • @akshayiithyd

    @akshayiithyd

    5 ай бұрын

    Really liked the O(1) explanation, thanx. Can you make the video explaining what does the term amortized exactly mean, can we assume it as same as avg time?

  • @sanjaycse9608

    @sanjaycse9608

    5 ай бұрын

    ​@@akshayiithydno that was constant time operation

  • @va11bhav_rana

    @va11bhav_rana

    5 ай бұрын

    honestly, i only do Leetcode just when you do, so please don't stop

  • @KhyatiSatija

    @KhyatiSatija

    5 ай бұрын

    no its perfect.

  • @singletmat5172

    @singletmat5172

    5 ай бұрын

    I appreciate the longer explanations, it’s very thorough and it clears a lot of confusion for me. And I also appreciate you mentioning that you wouldn’t be able to solve it if you did it for the first time. 😅

  • @servantofthelord8147
    @servantofthelord8147Ай бұрын

    I used to watch your videos on 1.5x speed, yet I always had to rewind because I kept missing the logic. Once I humbled myself and decided to slow it down to 1x speed - I have a much more thorough understanding of your content. THANK YOU!

  • @utkarshchaturvedi2405
    @utkarshchaturvedi24055 ай бұрын

    Found out today that you solve daily problems , will be following these videos from today♥

  • @garsidrag
    @garsidrag5 ай бұрын

    i think you should really consider changing it up and once in a while instead of saying its pretty efficient, you should say its hella efficient. would be very satisfying to hear.

  • @Amy-601
    @Amy-6015 ай бұрын

    Literally just solved it today after 4 years. I think it was daily challenge or something. I remembered to push onto in-stack and pop from outstack, checking if it’s empty and doing an outstack.push( in stack.pop()). Lol 😂. But I liked your “ amortized” explanation, didn’t think of “ amortized”. - Amy

  • @davidkent5749
    @davidkent57495 ай бұрын

    Plz add this question to neetcode all on ur website it will be really helpful.

  • @krateskim4169
    @krateskim41695 ай бұрын

    Great video

  • @chien-yuyeh9386
    @chien-yuyeh93865 ай бұрын

    Nice🎉🎉

  • @garth2356
    @garth23565 ай бұрын

    Great solution and explanation but this shouldn't be an *easy* question :(

  • @Zefn1x
    @Zefn1x5 ай бұрын

    Man fuked up google’s Interview. Will be grinding your sheet and doing LT contests. Thanks for your explanation! ❤

  • @jeffraj9937

    @jeffraj9937

    5 ай бұрын

    Same here messed up with a simple question. Started grinding Daily..

  • @tizekodnoon8305
    @tizekodnoon83055 ай бұрын

    Neato! Brain fried! 🧠🤯

  • @pastori2672
    @pastori26725 ай бұрын

    nice

  • @michaelyao9389
    @michaelyao9389Ай бұрын

    How to come up with this idea...

  • @sourabpramanik996
    @sourabpramanik9965 ай бұрын

    Do you think it is possible to do it using one stack only (if there is a follow up question)? I think it is possible but it won't be memory efficient I guess

  • @arturpelcharskyi1281

    @arturpelcharskyi1281

    5 ай бұрын

    You can. I came up with 2 ways: 1. Create a pointer that will refer to the element that should be returned when the pop() or peek() function is called. If we call pop(), we move this pointer forward by 1 element. In push() we add elements to the end of the list, and in the function empty() we return: pointer == len(stack). 2. If you write in Python, you can set the stack as a list, and when you call pop(), return the result of pop(0). Then 0 element will be removed from the list and its value will be returned. If we compare these two methods, the first requires more memory, but all functions are executed in O(1), the second method uses less memory, but the pop() method can take O(n) time depending on the specifics of the implementation remove 0 item from list in different languages.

  • @leeroymlg4692

    @leeroymlg4692

    5 ай бұрын

    @@arturpelcharskyi1281 that's breaking the rules, because in a stack, you can only look at the top of the stack (the last element)

  • @sourabpramanik996

    @sourabpramanik996

    5 ай бұрын

    @@arturpelcharskyi1281great solve. I solved using the first approach

  • @shaanvijaishankar5314
    @shaanvijaishankar53142 ай бұрын

    Why is this video not listed in 'Neetcode All'?

  • @mikerico6175
    @mikerico61755 ай бұрын

    @NeetcodeIO , you should create a private method to avoid duplucate code lines 11 and 17

  • @NeetCodeIO

    @NeetCodeIO

    5 ай бұрын

    I prefer WET (write everything twice) over DRY (don't repeat yourself) 😝

  • @michael._.

    @michael._.

    5 ай бұрын

    TIL what WET and DRY meant... learning something new every time I watch neetcode's videos

  • @dera_ng

    @dera_ng

    5 ай бұрын

    ​@@NeetCodeIO 🫠

  • @brucem8448
    @brucem84485 ай бұрын

    Queues are FIFO. Stacks are LIFO. Queue, original order: user1, user2, user3 Queue, popping: user3, user2, user1... Queue popping reverses order. This is why 2 (!) queues are necessary - reversing reversal preserves the original order 🙂

  • @ooouuuccchhh
    @ooouuuccchhh5 ай бұрын

    in the peek method, you can just return the first element of the stack1 rather than again popping and appending the elements. it can go like if not self.s2: return self.s1[0]

  • @mzafarr

    @mzafarr

    5 ай бұрын

    But that violates property of stack, because in stack you can only access the last element.

  • @ooouuuccchhh

    @ooouuuccchhh

    5 ай бұрын

    @@mzafarr got it!

  • @Baseballchampion

    @Baseballchampion

    5 ай бұрын

    See 11:20

  • @dumbfailurekms
    @dumbfailurekms5 ай бұрын

    When I first started watching your videos I would probably look at this problem and take some time to do the O(n) solution. After about a year of practicing, there was literally not a microsecond that I even considered to solve it in O(n) because I instantly realized that would be trivial and the only real problem is doing this in amortized O(1). point is you helped me a lot to grow

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