Rotate Image (Leetcode 48) | Full solution with examples visuals and animation | Study Algorithms

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  • เผยแพร่เมื่อ 10 ม.ค. 2025

ความคิดเห็น • 53

  • @madhukumar313
    @madhukumar313 2 ปีที่แล้ว +29

    I really don't know why youtube is not recommending your videos in the top list...excellenet way of explaining the problem and the solution...starting with brute force method to optimized and then dry-run of the code...best videos ever...keep the videos rolling....don't get bogged down by the view counts...

    • @nikoo28
      @nikoo28  2 ปีที่แล้ว +4

      Thank you so much for the love. I hope youtube starts showing my videos on the top soon 😄

  • @sushmas660
    @sushmas660 ปีที่แล้ว +4

    I don't usually leave comments. . So far, I haven't seen such a thorough explanation. thank you very much, sir

  • @anujgupta1484
    @anujgupta1484 11 หลายเดือนก่อน +1

    Bro you are truly a Gem for the coder community your explanation and teaching of each point are very understandable form.

  • @kundrapuharika6294
    @kundrapuharika6294 ปีที่แล้ว +3

    A very few can explain with real life examples and I am happy to find this channel which are very informative👏

  • @justinking684
    @justinking684 ปีที่แล้ว +2

    I was stuck in this problem almost a day to solve without transposing, after watching this I was clear now, Thanks bro, keep uploading videos

  • @impulse1712
    @impulse1712 หลายเดือนก่อน +1

    Honestly speaking sir, you are one of the top well explained persons on the youtube, i really loved your way of explanation, thank you so much and keep doing many such things for us.

    • @nikoo28
      @nikoo28  หลายเดือนก่อน

      You are most welcome

  • @anshika_1208
    @anshika_1208 17 วันที่ผ่านมา

    best teacher for coding❤

  • @rishav-ranjan
    @rishav-ranjan 2 ปีที่แล้ว +2

    this explanation helped me a lot

  • @eminentm1655
    @eminentm1655 2 ปีที่แล้ว +2

    much appreciated Sir, thanks.

  • @vishwasankar14
    @vishwasankar14 11 หลายเดือนก่อน +1

    Thank you! You are the best man!

  • @arjunjadhav6275
    @arjunjadhav6275 ปีที่แล้ว +2

    thanks for these ✨

    • @nikoo28
      @nikoo28  ปีที่แล้ว

      glad you found them helpful

  • @unemployedcse3514
    @unemployedcse3514 3 หลายเดือนก่อน

    I was above skip the vedio, but explanation is awesome ❤

  • @PoojaSharma0310
    @PoojaSharma0310 ปีที่แล้ว +2

    You solution is easy and straight forward. One question, why are you running loops (n+1)/2 and n/2? Thanks

    • @nikoo28
      @nikoo28  ปีที่แล้ว +1

      that is just because how we have to rotate the image. you need to visualize where the final pixels/integers will actually go. Then design your loop. So we are going one ring at a time. When you complete the first ring, you have already covered the first row and the last row. Hence the "/2".
      hope this helps.

  • @nirajkumaryadav365
    @nirajkumaryadav365 11 หลายเดือนก่อน +4

    in the second loop why you didnt use (n+1)/2 instead of n/2 ?

    • @gpraneeth7693
      @gpraneeth7693 5 หลายเดือนก่อน

      Same doubt bro

  • @shubhambarange
    @shubhambarange ปีที่แล้ว

    100% effect 100% Clarity

  • @EgorChebotarev
    @EgorChebotarev 2 หลายเดือนก่อน

    nice explanation

  • @krrishh7
    @krrishh7 6 หลายเดือนก่อน

    As always very descriptive and neat explanation bro👍
    Regarding the loop bounds, i think it would be best the inner loop(j) runs for +1 iteration, instead of the outer loop(i).
    So conceptually, from your logical explanation, for each ring which is the ith loop, all elements in the ring get rotated as part of the j iterations, then we move to the inner ring etc.
    But if we keep i loop for more iteration(N+1/2), for odd matrixes like 3*3 say, the inner ring is just 1 element, so ideally there shouldn't be a second ring to be rotated/fixed (as its only 1 element matrix[1][1]). but we can see here that the last rotation in the outer loop is happening as part of the inner ring (i=1) iteration (which ideally should have got completed as part of i=0 itself). If we keep j range from 0 to (N+1)/2, this will get fixed. Hope that makes sense.

  • @sysybaba420
    @sysybaba420 ปีที่แล้ว +3

    you have not explained how you came up with all the indices, however thanks for the final thoughts!

    • @nikoo28
      @nikoo28  ปีที่แล้ว

      the images where I show how a rotation takes place, defines the indices

  • @mehakdhiman5729
    @mehakdhiman5729 9 หลายเดือนก่อน +1

    Can you please explain how will the elements 9,7,14,2 get swapped when we are running the inner loop only till j < n/2 which in this case would mean that j=0 or j=1. What happens to the elements that are at j=2. How will they get swapped?

    • @nikoo28
      @nikoo28  8 หลายเดือนก่อน

      Watch the visual demo I have in the problem

  • @ksrinivasacharyulu873
    @ksrinivasacharyulu873 3 หลายเดือนก่อน

    Superb explanation bhaiyya....lekin problem solving logic kaise develop karna hai...ek video main bathado bhaiyya

  • @sibaathahmed1984
    @sibaathahmed1984 ปีที่แล้ว +1

    How u define limits as n+1/2 and n/2 respectively explain pls😢

    • @nikoo28
      @nikoo28  ปีที่แล้ว

      look at the part 7:10, 5 starts from 0 and reaches "n"
      If you run the loop to "n" then you will reach 5 again. We do not want that. We want to stop at middle. That is how the 4 way swap is working

  • @sanketsuryawanshi
    @sanketsuryawanshi 3 ปีที่แล้ว +1

    Thanks sir😇

  • @AnishMokashi-gz5kl
    @AnishMokashi-gz5kl 3 วันที่ผ่านมา

    also explain how did you took matrik[n-1-j] [i]

  • @ChaitanyaPimparkar
    @ChaitanyaPimparkar 3 ปีที่แล้ว +1

    of immense help

  • @ssss22144
    @ssss22144 หลายเดือนก่อน

    super brother

  • @ssnprakash
    @ssnprakash หลายเดือนก่อน

    it works for only square matrices, right?

  • @suneosama939
    @suneosama939 ปีที่แล้ว +2

    Brother can you explain for me why you know the syntax concept at each position, I understand thr concept you taugh but don't know how to write it in code ☹️☹️ how to know and write syntax at each position i wanna write 😢 so hard for me bro 😭, what is matrix[n-1-j] and matrix[n-1-i][n-j-1], matrix[j][n-1-i], and mattix[i][j] so hard brother

  • @nishanthsunkara1160
    @nishanthsunkara1160 10 หลายเดือนก่อน

    Could someone explain why the final elements (9, 7, 14, 2) in outer ring will get swapped, when we moved to inner ring i.e., i=1 but not when we are iterating at outer ring i.e., i=0 ?

    • @nikoo28
      @nikoo28  10 หลายเดือนก่อน

      please follow the explanation instead of going straight to the code.

  • @kavyakooks5305
    @kavyakooks5305 11 หลายเดือนก่อน

    I think the time complexity must be O(N) , as each cell is getting read once and written once.

    • @nikoo28
      @nikoo28  10 หลายเดือนก่อน

      correct, but we know that the edge size is n. So how many elements will you have? That is n^2
      Think like this, if the edge size is 5, then the area of square is 5^2 = 25.
      Since it is a cube, we have n^2 elements.

  • @xinyangli7103
    @xinyangli7103 8 หลายเดือนก่อน

    i understand why n/2 because in the inner layer we only need to do half, but i dont understand why outer layer is n+1/2 , shouldn't they be the same since column and row are the same dims?

    • @nikoo28
      @nikoo28  8 หลายเดือนก่อน

      Try to trace the path with the explanation I give. You will get the indices yourself.

  • @saurabhkukreja1982
    @saurabhkukreja1982 ปีที่แล้ว

    Can you explain the position of indices , its confusing where to consider n-1-i Or n-j-1 . Please explain
    Otherwise best explanation of the question

    • @nikoo28
      @nikoo28  ปีที่แล้ว

      walk through the explanation step by step. See how you are starting from outside and then going in 1 row/column at a time. Trace out and try printing the elements. That will explain everything.

  • @suneosama939
    @suneosama939 ปีที่แล้ว

    how to know the position likr bottom left is matrix[n - 1 - j][i]? It's hard to understand that and why above for loop (i < (n+1) / 2) and the second loop (j < n / 2), how do you know the syntax at each posititon top left top right bottom left bottom right, it's hard to understand 😢 can anybody explain how to know syntax at each posititon, omg so hard 😢☹️

    • @nikoo28
      @nikoo28  ปีที่แล้ว

      Take it step by step. Did you watch the entire video? I explain the thought process.
      Where to start and then where to end.
      What part are you facing a problem with?

  • @franly656
    @franly656 ปีที่แล้ว

    hi Nikhil Lohia, i have a question, how to rotate matrix 45 degrees so the matrix size will increase, i trying to make the solution and now i want to give up (i have tried straight 5 hours btw). Can you make this solution a video pls.

    • @nikoo28
      @nikoo28  ปีที่แล้ว

      haven't thought about a 45 degree use case. Can you find a sample question?

  • @vikshityadav9886
    @vikshityadav9886 3 หลายเดือนก่อน

    bhai dry run smjh aa jata hai per code smjh nhi aata thoda smja diya kro

  • @omsudhamsh.h
    @omsudhamsh.h 7 หลายเดือนก่อน

    ok simple
    firstly Transpose the given matrix and then reverse it.
    -------------------------------------------------------
    Runtime
    0
    ms
    Beats
    100.00%
    of users with Java

  • @Nature_Lover_Animal_Lover
    @Nature_Lover_Animal_Lover หลายเดือนก่อน

    Bit more explanation is needed in the for loop

  • @mayankpathak6827
    @mayankpathak6827 6 หลายเดือนก่อน

    sir you are doing awesome but your voice of video is very low

    • @nikoo28
      @nikoo28  6 หลายเดือนก่อน

      i have fixed that in my latest videos. Check them out and please let me know