Dijkstra's algorithm in 3 minutes

Поділитися
Вставка
  • Опубліковано 25 сер 2024
  • Step by step instructions showing how to run Dijkstra's algorithm on a graph.
    Code: github.com/msa... (different than video, I added this retroactively)
    Source: Algorithms by S. Dasgupta, C. H. Papadimitriou, and U. V. Vazirani [www.amazon.com...]
    LinkedIn: / michael-sambol

КОМЕНТАРІ • 373

  • @rahulsonwalkar3663
    @rahulsonwalkar3663 7 років тому +3964

    When you had an entire semester to study but you delay it till the last hour.

    • @ObradovacPower
      @ObradovacPower 6 років тому +45

      SO TRUE HAHAHA!!!!! lmao

    • @BiancaDianaT
      @BiancaDianaT 6 років тому +17

      On point ._.

    • @haoranlou155
      @haoranlou155 5 років тому +17

      气死我了,被抓包了

    • @JHmuniz1
      @JHmuniz1 5 років тому +19

      30 min*

    • @phylmath
      @phylmath 5 років тому +23

      So damn true, my exam is in twenty minutes lol.

  • @LevyaFox
    @LevyaFox 2 роки тому +731

    I just learned more in that 3 minutes than the last 2 weeks of my programming class. Thanks a lot! :)

  • @ThisClark
    @ThisClark 9 років тому +495

    mikey, keep it up. you're cutting the other videos down by minutes - it's super efficient to study with you

    • @MichaelSambol
      @MichaelSambol  9 років тому +58

      James Clark Thanks, James. More coming soon.

    • @psibarpsi
      @psibarpsi 8 місяців тому +3

      An implication of Parkinson's Law.

  • @Tombalino
    @Tombalino 8 років тому +122

    Finally a clear, short and simple explanation :)
    On behalf of everyone, thankyou and good job

  • @sumitsapkota3792
    @sumitsapkota3792 7 років тому +428

    What my teacher teach for whole semester I can learn over a night on UA-cam. Why the hell I am paying my semester fee, Instead I should pay for high speed broadband.

    • @ROFEL
      @ROFEL 5 років тому +47

      what kinda teacher teaches dijkstra's algorithm for a whole semester?

    • @ramimxss
      @ramimxss 4 роки тому +15

      @@ROFEL he meant everything his University or college covered in a semester,he is right though, sometimes

    • @SuperBhavanishankar
      @SuperBhavanishankar 4 роки тому +1

      @@ramimxss s

    • @loot6
      @loot6 3 роки тому +12

      There isn't anything you can't learn faster and more easily at home with the internet - all you need is motivation.

    • @blazingsniper1239
      @blazingsniper1239 3 роки тому

      ​@@loot6 so true

  • @emresarac2100
    @emresarac2100 2 роки тому +57

    It's crazy the fact that a 3 min video teaches me way better than a 1 hour class video of my teacher. Why do teachers always struggle with teaching in a simple way?

    • @BossKing1243
      @BossKing1243 Рік тому +29

      A lot of them become teachers bc they’re really intelligent and hardworking, not because they’re actually good at teaching

    • @Omenemperor2
      @Omenemperor2 10 місяців тому +7

      @@BossKing1243 Can't agree more, most of them are good at doing research rather than teaching us

    • @harshsason3725
      @harshsason3725 8 місяців тому

      @@BossKing1243 Yup exactly.

    • @adriangjonca680
      @adriangjonca680 2 місяці тому

      Also classes move at the pace of the slowest learner. While videos go at superspeed, knowing you can just rewind a section you don't understand.

  • @iizvullok
    @iizvullok 7 років тому +139

    You just needed 7 minutes (actually less) to explain everything I did not understand in more than 3 hours! Thank you!

    • @AB-ld1rp
      @AB-ld1rp 7 років тому +4

      Excuse me for using your top comment, but I have to let people see this: Sorry, but this algorithm is incomplete and not capable of solving a problem that my professor gave me. It works for the simplest matrices, but that's that. As a proof try to solve this exercise as said in the video:
      find the shortest route from f to c. The matrix is:
      . a b c d e f
      a 0 2 4 0 0 5
      b 9 0 0 7 5 0
      c 4 3 0 8 0 0
      d 0 3 9 0 0 6
      e 6 0 0 5 0 0
      f 0 5 0 6 3 0
      The solution should be 13 (f-e-a-c) but with this algorithm you will never obtain it.

    • @JoMaFjErynMaLaZOr
      @JoMaFjErynMaLaZOr 7 років тому +1

      worked for me

    • @VandamePlays
      @VandamePlays 6 років тому +21

      There is an error in this explanation, I actually learnt the base of the algorithm here since the explanation is very simple and I came to find that it wasn't completely right. The error is when he says that we choose the edge with the minimal cost in order to visit a certain node, that's not the case, we have a list of the unvisited nodes and from all those nodes, the algorithm says that the next node to be visited is the node with minimal TOTAL distance to the origin, remember every visited node tries to update the adjacents nodes.
      You wrote this a long time ago, but I hope new viewers don't fall for the same mistake I did when I only based in this explanation.

    • @Khaleb_0
      @Khaleb_0 6 років тому +4

      but if that's the case where's his mistake? he always chooses the "cheaper" one realtive to the origin? or are you saying that his wording was poor?

    • @OrnateOwl
      @OrnateOwl 6 років тому +3

      I believe he's talking about the wording. The lack of explanation about how he did what he did for the sake of simplicity.

  • @fitwithrmj
    @fitwithrmj 7 років тому +143

    bro u save me just 13 hrs before my exam...

  • @rayryeng
    @rayryeng 3 роки тому +9

    Someone who can actually take on Siraj Rival's mantra of learning something in 3 minutes lol. Very well explained, especially for someone who has seen this before but needed a quick refresher. Thanks so much!

  • @JonathanRose24
    @JonathanRose24 6 років тому +16

    Getting ready for an interview and this is EXACTLY what I needed. THANK YOU!

  • @z.m.4331
    @z.m.4331 7 років тому +8

    You're exactly the type of human the internet needs! Thank you!! :D

  • @prasp999
    @prasp999 2 роки тому +3

    I've been almost a month learning it and still don't understand what it is. Now you can make me understand in 3 minutes. I love you and thank you. God bless you!!

  • @tiannawrona9269
    @tiannawrona9269 4 роки тому +4

    I've been watching hours of lecture videos talking about these and haven't understood them until your 2-3 minute videos! Thanks! Much less stressed now.

  • @antonhall2696
    @antonhall2696 9 років тому +35

    This is great! Short, simple and very easy to follow. I like that you've made the pictures beforehand and don't draw freely during the video.
    Liked and subscribed :)

  • @farzaadify
    @farzaadify 9 років тому +18

    This is like a quick revision during exams,Thank you .

    • @ethandenson7182
      @ethandenson7182 6 років тому

      do you mean review?

    • @pkgamma
      @pkgamma 5 років тому +6

      why tf do you have access to UA-cam during exam

  • @kevinqagish2287
    @kevinqagish2287 8 місяців тому +3

    Alter Geile Meile ich bin die Ganze Zeit am versuchen die Funktion Anhand meiner Vorlesungsmaterialen zu verstehen und komm 0% vorwärts ... Ich gehe auf UA-cam schaue mir ein 3 Minuten Video and und verstehe es direkt! Vielen Dank!! Das Video is sau stark !!!

  • @easyas-is
    @easyas-is 7 місяців тому +1

    2024 here and you are a genius for explaining the algo so clear

  • @matejpersic6601
    @matejpersic6601 4 роки тому +1

    bro for the last two years I come back to this video every once in a while because I need it for a different class.. Thanks, you're awesome :D

  • @forever_stay6793
    @forever_stay6793 3 місяці тому

    I showed up an hour late to class and missed the explanation for this. This 3 minute video explained everything I needed to know thank you!

  • @Majestic469
    @Majestic469 4 роки тому +2

    This is actually legend. I searched up many long videos explaining it but only this short one helped me understand

  • @MidnightBloomDev
    @MidnightBloomDev 4 роки тому +18

    When you have 30 minutes before final semester exam but you didn't study at all

    • @adriangjonca680
      @adriangjonca680 2 місяці тому

      LMAO I'm here the day before my ALevel CS exam.

  • @MyNguyen-ln1dv
    @MyNguyen-ln1dv 7 років тому +2

    You seriously need to make more videos about algorithm. They help me sooooo much. Thanks a lot

  • @nawdawg4300
    @nawdawg4300 5 років тому +2

    These 2 min reviews are a god send! Final in 3 hours...

  • @d_asude
    @d_asude 2 місяці тому +1

    Thanks to you, I finished 4 different topics 1 hour before the exam 😀

  • @danielalvarez9404
    @danielalvarez9404 6 років тому +1

    Dude, I love you

  • @mrsword6493
    @mrsword6493 2 роки тому +1

    I like how those videos are 2-3 minutes but it always take me 15+ minutes to watch them to the end

  • @livea404life
    @livea404life 2 місяці тому

    Thx! You helped me passing algorithm course exam last year, and I believe this video can help me passing the network course exam again!

  • @TheJunkieBox
    @TheJunkieBox 7 років тому +2

    Short and sweet. We need more videos like this.

  • @Kaira_edits8
    @Kaira_edits8 2 місяці тому

    I felt so stressed for the exam coming in three days, and now I found your channel explaining everything so simply, thank you ❤

  • @E_D___
    @E_D___ Рік тому

    most Teachers in Uni are so focused on proving the algorithm works, and is the best way to do 'X' - to the point they dont notice, or care, if the students even understood what the algorithm does or even supposed to do.
    thank you

  • @thealiens386
    @thealiens386 Рік тому

    Even 8 years later you're still saving lives with this

  • @ogCharaLM
    @ogCharaLM 8 років тому

    Thank you for this. There aren't enough truly concise videos out there, and I was getting desperate.

  • @thanasulas08111994
    @thanasulas08111994 10 років тому +28

    Simple and well explained. Thank you very much!
    It would be really great if you could make a video for Bellman-Ford algorithm too.

    • @MichaelSambol
      @MichaelSambol  9 років тому +8

      thanasulas08111994 ***** Working on it now!

    • @MichaelSambol
      @MichaelSambol  9 років тому +28

      ua-cam.com/video/obWXjtg0L64/v-deo.html

  • @davidwong666
    @davidwong666 4 місяці тому

    Gonna have my final exam in 15 mins and I am here reivising the last topic taught in the lecture. Thanks!

  • @godsepicgamer3825
    @godsepicgamer3825 Рік тому

    EVERYONE explains this so hard this REALLY helped me thank you

  • @mr.paarthurnax2649
    @mr.paarthurnax2649 3 роки тому +2

    This explanation was awesome! So simple and concise. Thanks!

  • @epiclasersharks1866
    @epiclasersharks1866 3 роки тому

    your videos are the best. Nobody wants to watch a 20 minute video just to pass their exam

  • @li-pingho1441
    @li-pingho1441 3 роки тому +1

    The best tutorial ever

  • @matthewblom1620
    @matthewblom1620 Рік тому

    Incredible video. Thank you you hero. So many videos of 20 minutes + that cannot get to the point.

  • @audiomac
    @audiomac 9 місяців тому

    My textbook never told me what "cost" was. It randomly started using that term. Thanks!

  • @indianpublic4543
    @indianpublic4543 6 років тому +2

    best videos ever .... to understand data structure in few minutes ..
    make more videos
    ..plz

  • @georgeoneal3641
    @georgeoneal3641 Рік тому +4

    Thanks a whole lot. However, from 1:41 why do we use the weight 3 instead of weight 1? That is the only thing I do not seem to understand. Thank you in anticipation of your response.

    • @w花b
      @w花b 9 місяців тому

      I don't understand what you're asking but one thing to keep in mind for others that might see your comment is that we add the value of the node you're in to the value of the node you want to go to and compare that result to the current value in your node list for the one you want to reach. If it's infinity then you place it but if it's equal or smaller than your sum then don't change it.

  • @YouB3anz
    @YouB3anz 3 роки тому

    This psuedocode rendition is nice, compact, and readable. Much better than a lot of the other ones you see.

  • @kamadaichii
    @kamadaichii Місяць тому

    i hope this comes clutch for me learning it from scratch for a semester exam tomorrow.

  • @dirtworm979
    @dirtworm979 Рік тому

    Thank you! I fell asleep during my lecture, this was a lifesaver!!

  • @ozancngz
    @ozancngz 3 роки тому

    It was the most useful 3 minutes in my life . Thank you.

  • @tangdexian3323
    @tangdexian3323 6 років тому

    I really like your approach, concise and to the point

  • @skelswap
    @skelswap 4 місяці тому

    had to catch up after not going to a lecture, but i cant imagine how tf it took an entire lecture to explain this and one other algorithm

  • @Bred0nSch00lV2
    @Bred0nSch00lV2 5 років тому

    A nice condensed little video. Thank you.

  • @marcosangelmedina5845
    @marcosangelmedina5845 Місяць тому

    I have nothing against indian guys, they are smart and great people... But listening to an American English speaker is a pleasure to my ears.

  • @SupunKandambige
    @SupunKandambige Рік тому +2

    Watched it for an interview, when I went for the like button, I noticed that I already liked it, probably from my BSc years. I never learn 😂😂😂

    • @MichaelSambol
      @MichaelSambol  Рік тому

      Welcome back, and thank you for watching! Good luck on your interview.

  • @drewkelly3622
    @drewkelly3622 8 місяців тому

    an algorithm my professor took 3 classes to explain and this dude didnt even need 3 minutes.

  • @24Ship
    @24Ship 5 місяців тому +1

    you're an angel

  • @JamesBrodski
    @JamesBrodski Рік тому

    Great video! Thank you so much for making it.

  • @jordancleeve7548
    @jordancleeve7548 8 років тому +4

    Awesome video thanks!

  • @ManhTran-ry9ux
    @ManhTran-ry9ux 4 роки тому

    OMG, finally all my semester can wrap up by approximately 3 minutes =)))

  • @brandoncazares8452
    @brandoncazares8452 Рік тому

    Thanks, Michael this video's very helpful.

  • @lalwho
    @lalwho 8 років тому

    cool video series for a quick recap before the exams...

  • @Siigrit
    @Siigrit 3 місяці тому

    Exam in 1 hour, thanks for this!

  • @creamsn3
    @creamsn3 Рік тому

    my prof recommended me to watch this instead him teaching. not because he lazy but this explaination is just good

  • @theamici
    @theamici 6 років тому +32

    U need to keep track of the paths and not just the values leading up to the nodes. Dijkstra's algorithm gives you a path with a value, not just a value.

    • @tarekadel7631
      @tarekadel7631 3 роки тому +1

      That's already been done in the video. You can obtain the shortest paths to each node by tracing the values in the "prev" Array/HashMap (shown in the pseudo code at the end).

  • @yusram.6175
    @yusram.6175 8 місяців тому +2

    I'm confused @1:33 why did D and E change to one less than what they were before?

  • @pedroraimundodossantosneto5846
    @pedroraimundodossantosneto5846 3 роки тому

    Concise and straight to the point. Thanks =)

  • @HuyPham-id7us
    @HuyPham-id7us Рік тому

    thank to your video! That video is better than my professor's lecture

    • @MichaelSambol
      @MichaelSambol  Рік тому +1

      You're welcome, Huy! Thanks for watching.

  • @aidan8465
    @aidan8465 10 місяців тому

    I can't believe I just found the Holy Grail of UA-cam channel for CS students

  • @Yawneazy
    @Yawneazy 2 роки тому

    thank you so much for this! Life changing

  • @leonellbais1659
    @leonellbais1659 4 роки тому

    you deserve a plenty of likes dude. i like how you shorten the video for us ❤️

  • @kaliferguson2232
    @kaliferguson2232 Рік тому

    Very clear explanation. Thank you!

  • @andywei5518
    @andywei5518 5 років тому

    unsw trimester is very busy, but thanks, you saved me a lot of time ~ ! ! !

  • @bunpun5135
    @bunpun5135 3 роки тому +1

    michael you beautiful man you've saved me from an awful grade

    • @inigo1880
      @inigo1880 3 роки тому

      Guess who's nearing the awful grade now :)

  • @gedeonandrasmusic
    @gedeonandrasmusic 6 років тому

    Very great, thanks for your help!

  • @sarveshpandey1125
    @sarveshpandey1125 6 років тому

    It's such a perfect explanation.

  • @TFTAlecUchiha
    @TFTAlecUchiha 4 роки тому

    You are such a king

  • @AACVOMMIDHARANI
    @AACVOMMIDHARANI Рік тому

    Thank you soomuch yaar you made my day much better

  • @lolejunior3168
    @lolejunior3168 3 роки тому

    My g saving people life right now

  • @nemanjabosko
    @nemanjabosko 11 місяців тому

    I passed algoritm class because this man

  • @Shkencetari
    @Shkencetari 6 років тому

    Great tutorial. Thank you very much.

  • @cantorbernoulli4407
    @cantorbernoulli4407 2 роки тому

    my man thanks for saving me time

  • @theningdynasty
    @theningdynasty Рік тому

    i wasnt sure wgat the differnce between this and bfs is. thank you so much!! 💅

  • @semoreyad2933
    @semoreyad2933 6 років тому

    good , simple and clear explanation , thank you :D

  • @kp7jim
    @kp7jim 6 місяців тому

    This vid is the way I'm passing my Computer Networks class tmr

  • @LioHmusic
    @LioHmusic 6 років тому +1

    Exam saver!! Thanks

  • @kevinzhang7228
    @kevinzhang7228 7 років тому +1

    Your videos are great!

  • @houssemdhiab7337
    @houssemdhiab7337 8 років тому +1

    thank you dude for saving my life :D

  • @chiminim424
    @chiminim424 7 місяців тому

    Bro u truly are the best keep up 🔥

  • @digvijayandhorikar936
    @digvijayandhorikar936 8 років тому

    GOod..fantastic.It was like the fastest way..PErfect man keep it up!!!!!!

  • @davidboublil
    @davidboublil 8 років тому

    thank you so much!!! You saved my life (again)

  • @calebkrauter4027
    @calebkrauter4027 Рік тому

    This is so good. Thanks!

  • @godisgreat9749
    @godisgreat9749 2 роки тому

    thank you, straight to the point,

  • @ognjensimic5042
    @ognjensimic5042 6 місяців тому

    Hvala brate moj!

  • @zakyoung2374
    @zakyoung2374 2 роки тому

    I have my exam in 30 minutes this is perfect

  • @jimkash7133
    @jimkash7133 6 років тому

    a truly inspired work 10/10

  • @ChaoZonic
    @ChaoZonic 8 років тому

    Thanks for the excellent video: I now know how to pronounce Dijkstra!

  • @learnfullstackqaonline
    @learnfullstackqaonline 8 років тому

    thanks! this really helped me a lot!

  • @kautukraj
    @kautukraj 4 роки тому +1

    Very helpful!

  • @MYY-on5rk
    @MYY-on5rk 4 місяці тому +1

    I believe there might be an error in your results at 2:09. Shouldn't the path sequence be A -> C -> B -> E -> D, instead of both B -> E and B -> D? Following the A -> C -> B -> E -> D route results in a total cost of 7, rather than the cost of 8 that was concluded. Could you please verify this?

    • @amiraayedi
      @amiraayedi 3 місяці тому

      exactly my thought

  • @ubaidurrehman4377
    @ubaidurrehman4377 6 років тому +1

    Thanks, good Tutorial

  • @Daniel-iy1ed
    @Daniel-iy1ed Рік тому

    You are amazing man 🤩🤩

  • @josemunguia5660
    @josemunguia5660 6 років тому

    Great video! Thanks!

  • @andrejtrozic9476
    @andrejtrozic9476 2 роки тому

    Sir...thank you very much!