Dijkstra's Algorithm (Decision Maths 1)

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  • Опубліковано 9 січ 2025

КОМЕНТАРІ • 114

  • @riomilano9350
    @riomilano9350 4 роки тому +2

    Out of all the tutorials that I've found, yours was the best one. Thanks

  • @patrickmorriss
    @patrickmorriss 5 років тому +1

    This might be have been uploaded 7 years ago, but it is still extremely helpful. Clear, concise, perfectly explained - I now completely understand this algorithm. Dude - thank you - so much.

  • @nurilha
    @nurilha 9 років тому +2

    Fantastic explanation! I have the task of programming this for my MSc to find shortest path for routes on London underground. Good refresh as I last sat this exam in 2008.

  • @YusufMaths2010
    @YusufMaths2010 11 років тому

    you explianed better than my teacher and got the correct answer for the last one.... thank you man...

  • @noctisocculta4820
    @noctisocculta4820 11 років тому +3

    Wow thanks for this, I think I finally understand this algorithm thanks to you. The way you explain it by doing it by hand with those 3 boxes by each node finally let me click into what's going on with opening and closing node lists.
    Cheers mate, this was extremely helpful.

    • @HEGARTYMATHS
      @HEGARTYMATHS  9 років тому +1

      Noctis Occulta Hiya - thanks loads!!! A favour to ask....Any chance you could spare 30 secs to vote for HegartyMaths in this Richard Branson competition which ends in a few days. Would mean a lot to me and HegartyMaths. www.virginmediabusiness.co.uk/pitch-to-rich/start-up/hegartymaths/ Thanks Mr H

    • @noctisocculta4820
      @noctisocculta4820 9 років тому +1

      HEGARTYMATHS
      It is done

  • @baadshahnitin
    @baadshahnitin 12 років тому

    It Helped Me Alot...I Never Went To lectures In Uni... Exam Time I Searched...Selected This One....Trust me Aint Dissapointed...Learnt It First Time...:D :-) :D

  • @polyroguegames5820
    @polyroguegames5820 7 років тому

    Coming back to this now as a second year computer science student - memories! This is still a helpful clear refresher! Thanks!

  • @HEGARTYMATHS
    @HEGARTYMATHS  11 років тому

    You are most welcome! Glad if my video helped! Cheers. Mr Hegarty

  • @TheWackyParrot
    @TheWackyParrot 9 років тому

    Quick note to say thanks for this. Makes learning D1 much, MUCH easier. Good luck on your Branson campaign, might have missed the shortlisting but if you need votes in the future just give a shout.

  • @Sami644
    @Sami644 12 років тому +1

    omgggg I love his teaching and exampling style... I just loved the assignment problem he gave us in the end.. haha wowww thank you sooooooo much!!! HATS OFF FOR YOU :)

  • @HEGARTYMATHS
    @HEGARTYMATHS  11 років тому

    Hi Bob - thanks laods for the comment. Really delighted to help and remember there are loads more videos to help with your maths and decision maths at hegartymaths.c.o.m. Best wishes. Mr Hegarty

  • @HEGARTYMATHS
    @HEGARTYMATHS  11 років тому

    That's why you work backwards at the end to determine the shortest path as this finds the exact one for you.

  • @Dan0812
    @Dan0812 12 років тому

    Great video, got my exam in 10 hours so very helpful!

  • @HEGARTYMATHS
    @HEGARTYMATHS  11 років тому

    Cheers. Glad to have helped! Mr Hegarty

  • @miked.7972
    @miked.7972 10 років тому +1

    That was an incredibly helpful presentation. Thank you very much!

  • @xxveskoxxbg
    @xxveskoxxbg 11 років тому

    Hi. Thank you for taking your time in making this tutorial. Its highly appreciated.

  • @blownupdogsify
    @blownupdogsify 8 років тому

    This channel helped me so much last year in my GCSEs and I got an A in maths, now I'm doing AS maths and further maths in college and I happen to stumble across this channel again.
    Thank you so much for your videos they are really helpful.

  • @Absieee
    @Absieee 9 років тому +2

    Thank you very much for explaining this so much better than my lecturer! :)

    • @HEGARTYMATHS
      @HEGARTYMATHS  9 років тому +1

      Absieee Delighted to help Absieee - would you be able to spare 30 secs to help me out by voting for my new website coming soon here. Thanks loads - it would mean a lot. Mr H www.virginmediabusiness.co.uk/pitch-to-rich/start-up/hegartymaths/

    • @Absieee
      @Absieee 9 років тому

      HEGARTYMATHS Consider it done, Mr. H.

    • @HEGARTYMATHS
      @HEGARTYMATHS  9 років тому +2

      Absieee You're a star

  • @francescasala3332
    @francescasala3332 11 років тому +3

    Hi,
    I just wanted to say thank you so much! I´m studying in Munich at Technische Universität München and we have a lecture it is called Management Science our professor didn´t tell us about a pattern like this I wonder why.
    Kind regards from Germany

  • @J97H51
    @J97H51 9 років тому

    Thank you so much! This video cleared up all my confusion about this algorithm

  • @adityaacharya3905
    @adityaacharya3905 11 років тому +1

    Thanks Man, It's a good one, only one doubt. While marking a node permanent can't we mark there the last node connection path, like when changing D value from 18 to 17 if we can also add Value B to denote that the path came here is from B. Then we don't have to do the last tracing steps, we can easily take from where it is coming.
    And I think it will be easy to implement in the code

  • @QBrute_
    @QBrute_ 11 років тому

    Instead of labelling the nodes with numbers for the nth label, you could just write down the node you came from for that current node. So when backtracking you just have to read what nodes you came from and don't have to iterate through all adjacent ones for fitting distances. :)

  • @EmilySmith-xk6vp
    @EmilySmith-xk6vp 12 років тому

    Maybe for a specific class or exam you're required to mis-use that diagram, BUT...
    The top left box should be used for recording the parent. When you affix the permanent label, use the top left box to record the previous spot. Then it is easy to retrace your steps to find the overall path. Your method of figuring it out is both time-consuming and dangerous. What if there were six (or 60) choices of previous spots all 2 units away. How would you choose?

  • @HanaDivya
    @HanaDivya 10 років тому

    Q-In example 1, when tracing back, can you go from D to F as 7-5=2, which is also the weight of the arc?

  • @rachitranjan
    @rachitranjan 11 років тому

    Cool Tutorial ..I wanted to know what if we applied Dijkstra's Algo to graphs with negative edges but no -ve cycle .

  • @HEGARTYMATHS
    @HEGARTYMATHS  11 років тому

    Thank you and you're very welcome!

  • @Joredos
    @Joredos 11 років тому

    I was quite confusing in Dijkstra but with this easy going video I am doing well with :) .Thanks :)

  • @nishasunny8762
    @nishasunny8762 12 років тому

    gud explanation........very clear...easy to understand....thnk u......:-)

  • @Ultrasonix3
    @Ultrasonix3 4 роки тому

    Godly explaination. Thank you good sir

  • @HEGARTYMATHS
    @HEGARTYMATHS  11 років тому

    You are most welcome! Thanks for the feedback. You will find more videos of use at hegartymaths.c.o.m. and ones like this in the Decision Maths section within A-Level Maths. Best wishes. Mr Hegarty

  • @shreyansgupta4457
    @shreyansgupta4457 6 років тому

    Hj, which software can i use to make the graph and get the boxes to work through the algorithm on a computer?

  • @TheGregcawthorne
    @TheGregcawthorne 11 років тому

    What if the starting nodes has 2 edges (vertices) coming off it which are weighted equally? If you choose one over the other you might not get the shortest path!

  • @juthamaspaiboonsak4296
    @juthamaspaiboonsak4296 11 років тому

    Thanks, made me understand about greedy algorithm

  • @dummmah
    @dummmah 12 років тому

    A tutorial that instantly made me "catch" the whole process after 2 days of pointless research. Hat down. =)

  • @mradamhowell
    @mradamhowell 12 років тому

    This is going to sound a silly question but why did you make b the 3rd distance and not d?

  • @miguelprincipegoods1906
    @miguelprincipegoods1906 6 років тому

    I need this same code, but in Visual Basic Excel. I intend to formalize a date or be a Matrix of distance between streets or houses in a city. Very urgently .. It is Dijkstra Algorithm.

  • @Ultrasonix3
    @Ultrasonix3 4 роки тому +2

    The textbook is so confusing for this one

  • @Aligndude
    @Aligndude 12 років тому

    Where I and D are the same value does it matter if I got I as node 5?

  • @Rajaudhaya
    @Rajaudhaya 12 років тому

    thank you so much sirrrrrrrrrrr..iam very wek student but i was easily understand

  • @venezuela5876
    @venezuela5876 10 років тому

    I don't understand, how can can the line EG be 2 inches and be longer than the line CE which is 5 inches long but shorter.

    • @TheMangaArtist96
      @TheMangaArtist96 10 років тому

      It's not based on the graphical representation, inches is just a way of representing the weights of the arcs. i.e. It's not drawn to scale. Hope that clears it up a bit.

  • @MikeCOYS
    @MikeCOYS 12 років тому

    My only difference is for C it is number 8, and G is number 7. But I still get the same answer, is that correct? Because there were two nodes with a path of 18, so I chose the one closest.

  • @ashiqwuzhere
    @ashiqwuzhere 10 років тому +1

    Very useful method! Thanks!

    • @HEGARTYMATHS
      @HEGARTYMATHS  9 років тому +2

      ashiqwuzhere Hiya - thanks loads!!! A favour to ask....Any chance you could spare 30 secs to vote for HegartyMaths in this Richard Branson competition which ends in a few days. Would mean a lot to me and HegartyMaths. www.virginmediabusiness.co.uk/pitch-to-rich/start-up/hegartymaths/ Thanks Mr H

  • @Darieee
    @Darieee 11 років тому +1

    Awesome video ! Thanks !

    • @HEGARTYMATHS
      @HEGARTYMATHS  9 років тому +1

      Darieee Hiya Dariee- thanks loads!!! A favour to ask....Any chance you could spare 30 secs to vote for HegartyMaths in this Richard Branson competition which ends in a few days. Would mean a lot to me and HegartyMaths. www.virginmediabusiness.co.uk/pitch-to-rich/start-up/hegartymaths/ Thanks Mr H

  • @0kontos
    @0kontos 11 років тому

    nice work! thank you for your time

  • @vaibhav1991feb
    @vaibhav1991feb 12 років тому

    yes we also create tables and stuff.....
    But this approach is better...

  • @MiroslavCsonka
    @MiroslavCsonka 12 років тому

    Why is it important to write down order, in which I label it as permanent? (sorry for bad english)

  • @robl39
    @robl39 11 років тому +1

    Awesome video thank you so much!!!

  • @robl39
    @robl39 11 років тому

    You are the man! Thanks buddy!

  • @derektetteh1608
    @derektetteh1608 10 років тому +1

    Do you have videos on standard form

    • @HEGARTYMATHS
      @HEGARTYMATHS  10 років тому

      Derek Tetteh Hi Derek - use the website as it's easier to find things here is standard form. Best wishes. Mr H www.hegartymaths.com/gcse/edexcel/secure-grade-c-in-higher/topics/v/gcse-revision-video-22-standard-form

    • @derektetteh1608
      @derektetteh1608 10 років тому

      Ok,thanks

    • @derektetteh1608
      @derektetteh1608 10 років тому

      On multiplying by 1,10,1000 isn't 3 x 43= 129?

    • @HEGARTYMATHS
      @HEGARTYMATHS  9 років тому

      Derek Tetteh Hiya Derek- thanks loads!!! A favour to ask....Any chance you could spare 30 secs to vote for HegartyMaths in this Richard Branson competition which ends in a few days. Would mean a lot to me and HegartyMaths. www.virginmediabusiness.co.uk/pitch-to-rich/start-up/hegartymaths/ Thanks Mr H

  • @aminator1
    @aminator1 8 років тому

    yay thanks, i understood it well, much appreciated :)

  • @arcadyt
    @arcadyt 12 років тому

    AWESOME EXPLANATION! THANKS!

  • @bentaylor3936
    @bentaylor3936 6 років тому

    Just a warning for people sitting their AQA D1 paper you can't do your workings out using this box method I got penalised for doing so and didn't get a single mark on this question and now have to do it again

  • @ShahRS87
    @ShahRS87 12 років тому

    nice explanation...thank you

  • @rianzamanx
    @rianzamanx 10 років тому +1

    Thanks a lot Really Very nice vid

    • @HEGARTYMATHS
      @HEGARTYMATHS  10 років тому

      Rian Zaman Hi Rian. Happ to help and be sure to check out www.hegartymaths.com/ and in particular www.hegartymaths.com/a-level/edexcel/decision-1 for more Decision Maths videos. Best wishes. Mr H

    • @HEGARTYMATHS
      @HEGARTYMATHS  9 років тому

      Rian Zaman Hiya Rian - thanks loads!!! A favour to ask....Any chance you could spare 30 secs to vote for HegartyMaths in this Richard Branson competition which ends in a few days. Would mean a lot to me and HegartyMaths. www.virginmediabusiness.co.uk/pitch-to-rich/start-up/hegartymaths/ Thanks Mr H

  • @chicokin
    @chicokin 11 років тому

    Thank you from Brazil. Helped a lot!

  • @AndyPusch
    @AndyPusch 11 років тому

    Thank you very much for this tutorial. :)

  • @jaydeepmeda6653
    @jaydeepmeda6653 9 років тому +1

    thanks man...!! you make this easy....;)

  • @turbothrottletrouble4217
    @turbothrottletrouble4217 6 років тому

    I am taking maths for a levels, should I take decision, and why is it hated soo much

    • @Ray_1337
      @Ray_1337 6 років тому +1

      I really think you should take decision. I don't know why people hate it. I absolutely love it. It just makes so much sense when you apply it to something in real life unlike most other things

  • @Zharkan16
    @Zharkan16 9 років тому +1

    great scot! thanks

    • @HEGARTYMATHS
      @HEGARTYMATHS  9 років тому +1

      Zharkan16 Hiya - thanks loads!!! A favour to ask....Any chance you could spare 30 secs to vote for HegartyMaths in this Richard Branson competition which ends in a few days. Would mean a lot to me and HegartyMaths. www.virginmediabusiness.co.uk/pitch-to-rich/start-up/hegartymaths/ Thanks Mr H

  • @JunminLingBlend
    @JunminLingBlend 11 років тому

    good tutorial, make complex concept easy and simple to understand.

  • @aw1lt
    @aw1lt 3 роки тому

    im using this in programming right now but i use hegarty in school haha

  • @bruinen89
    @bruinen89 11 років тому

    @fyaq5130 wow you learnt the shortest path real quick

  • @FarmYardGaming
    @FarmYardGaming 2 роки тому

    Helpful. Thanks.

  • @keyur1913
    @keyur1913 10 років тому +1

    Awsmlly helpfull..:)

    • @HEGARTYMATHS
      @HEGARTYMATHS  9 років тому

      Keyur Shroff Hiya Keyur- thanks loads!!! A favour to ask....Any chance you could spare 30 secs to vote for HegartyMaths in this Richard Branson competition which ends in a few days. Would mean a lot to me and HegartyMaths. www.virginmediabusiness.co.uk/pitch-to-rich/start-up/hegartymaths/ Thanks Mr H

  • @leonardoguevara9955
    @leonardoguevara9955 12 років тому

    Thank you so much !!!

  • @jaggoraj
    @jaggoraj 10 років тому +1

    Thanks a lot !!

    • @HEGARTYMATHS
      @HEGARTYMATHS  9 років тому +1

      Jagadish Kupanna Govindarajan Hiya Jagadish - thanks loads!!! A favour to ask....Any chance you could spare 30 secs to vote for HegartyMaths in this Richard Branson competition which ends in a few days. Would mean a lot to me and HegartyMaths. www.virginmediabusiness.co.uk/pitch-to-rich/start-up/hegartymaths/ Thanks Mr H

  • @ramashka19
    @ramashka19 11 років тому

    you are great!

  • @hamza3838
    @hamza3838 8 років тому

    Thank you so much

  • @vickeybhati
    @vickeybhati 12 років тому

    thanx a lot sir

  • @farouqueshabsug3470
    @farouqueshabsug3470 12 років тому

    Big like, and huge thnx :D

  • @TheGregcawthorne
    @TheGregcawthorne 11 років тому

    Ahh thanks! I forgot about that :P.

  • @Ajishuk27
    @Ajishuk27 10 років тому +1

    Thank you! This saved my ass. :)

    • @HEGARTYMATHS
      @HEGARTYMATHS  9 років тому +1

      Ajita Shukla Hiya Ajita- thanks loads!!! A favour to ask....Any chance you could spare 30 secs to vote for HegartyMaths in this Richard Branson competition which ends in a few days. Would mean a lot to me and HegartyMaths. www.virginmediabusiness.co.uk/pitch-to-rich/start-up/hegartymaths/ Thanks Mr H

  • @jtdabraham7638
    @jtdabraham7638 8 років тому

    helped a lot

  • @MsPersephone
    @MsPersephone 12 років тому

    Thanks!

  • @fidorf
    @fidorf 12 років тому

    thanks a lot

  • @wankxdd
    @wankxdd 12 років тому

    I am doing this at college XD

  • @TheRorojust
    @TheRorojust 12 років тому

    thank u soooooooo much

  • @amritadahiya102
    @amritadahiya102 11 років тому

    nice

  • @Stefan06091991
    @Stefan06091991 11 років тому

    what a champ

  • @tronmega2187
    @tronmega2187 11 років тому

    Thank you sir ,u jst saved me

  • @HEGARTYMATHS
    @HEGARTYMATHS  11 років тому

    Really kind comment! There loads more you might find useful at hegartymaths.c.o.m. - keep up the hard work.

  • @tummasjoensen
    @tummasjoensen 11 років тому

    very good tutorial, thank you :)

  • @nurilha
    @nurilha 9 років тому +11

    Fantastic explanation! I have the task of programming this for my MSc to find shortest path for routes on London underground. Good refresh as I last sat this exam in 2008.

    • @HEGARTYMATHS
      @HEGARTYMATHS  9 років тому +2

      +Nuril Ahmed You are totally welcome. Thanks for taking the time to say thank you. Best wishes and keep working hard! Mr H :-)

  • @everous_
    @everous_ 2 роки тому

    thank you so much