Shortest Path | Dijkstra's Algorithm Explained and Implemented in Java | Graph Theory | Geekific

[@manOfPlanetEarth]

Love author's distinct pronunciation👍🏼 He definitely thought about audience. And yes: material got really clear only in code. The gist is not a rocket sience but all mechanics comes in code.

[@vachadave1706]

Thank you, you make it so easy!

[@vietnguyenquoc4948]

Awesome explanations, how come youtube algorithm do not suggest this?

[@samarthtandale9121]

Amazing Content !!! How did you get your fundamentals so right at java, if there's a book I would like to know about it!

[@geekific]

Thanks man, glad I could help! There is no particular book, I research online and try to check as many references as possible and compare them. I try not to stick to one particular reference. Even if I am already knowledgeable in the topic of the video I am currently working on, I still do the research in order not to miss anything out and try to deliver everything that needs to be delivered :)

[@samarthtandale9121]

@@geekific That's great and very unique attitude ! Anyways just a friendly suggestion, when you explain a code snippet in terms of algorithm sometimes it's hard to find which part you are taking about .. so you can maybe highlight that portion for the moment I think, it's just my personal opinion ... But nevertheless I'm huge fan of your content and Thanks a lot 🙌🏼

[@geekific]

Will keep this in mind for future videos! Thanks for the feedback :)

[@mmm-ie5ws]

The code was hard to follow and you didnt give an explanation of how the algorithm is correct. Maybe for an expert who already knows this stuff this video would make sense.

[@geekific]

Sorry to read that! I would be happy to answer any question you may have regarding the video in the comments section :) Let me know!

[@aldo.express]

lol disagree, this java code is very readable, the naming convention is very simple and logical and the use of streams makes it much simpler than using a bunch of for-loops. If you're having a lot of trouble with the code part then make sure you pause and go line by line, and even with pen and paper if necessary, until you understand all the individual steps and can put them together.

[@Carrymejane]

U can search another resources

[@manOfPlanetEarth]

Hi, man again:))) Doing this algo with pen and paper I revealed some point for discussion. At some moment, especially for more connected graphs, both settled and unsettled collections begin to contain the same nodes☝🏼 Moreover, unsettled collection starts containing multiple duplicates of that same nodes. Yes, your realization still works right but all above brings some meaning disruption (especially simultaneous presence of some node in both collections opposite in their calling) and as for me I came up with two options to fix that. 1. Use TreeSet structure for unsettled list (then use pollFirst() method) 2. Do check: if(! unsettledNodes.contains(entry.getKey())) unsettledNodes.add(entry.getKey()); Your thoughts?:)

[@geekific]

That was a thorough investigation! Yup, I see no harm in either solutions :) Proud of you!

[@manOfPlanetEarth]

@@geekific Small disclaimer:) My only goal here is to grow. I am preparing for interview and every eminent company check ppl to REALLY understand algos and trees and graphs. No shallow touch will satisfy them😁 So I tend not to get off any topic until I get a feeling that I at least have no more questions for myself on this topic. That's why all my comments here are arising:)) Hope others may also find comments useful for them : watchers may see veiled aspects they would have overlooked otherwise, you receive thoughtful feedback and can deploy it at your discretion. We all always have smth to learn at least a little bit deeper😉 Plan to break down rest of graphs and all trees playlist. I feel more questions are coming:)))

[@geekific]

No worries man ask all you want, happy I can help! Good luck with your interviews :)

[@anjaliverma5834]

I need the code of it, from the given link of Github - it is difficult to get the correct code. Can u please provide it

[@geekific]

Hello! The particular code snippet for this algorithm wasn't yet pushed to GitHub, sorry about that :( We are working on keeping the repo as much as possible up to date. Stay Tuned!

[@glorysonhorace3265]

Thank you

[@SabbraCadabra11]

Hi! First of all, many thanks for the video, it's enormously helpful. I'm using this as a blueprint for my college assignment. However, I've got to write it in C# and I'm not that good in Java so could you please explain, how could I write this while loop in the calculateShortestPath method without using streams (can be still in Java)? Or at least how could I replace the .filter line when I'm not using stream?

[@geekific]

Hello! Glad it was helpful :) The filter is basically an if-statement inside a for-loop. Or you can download a Java IDE (I use IntelliJ) and it will help you easily convert between streams and loops! (Alt+Enter on the stream keyword or for keyword for options) Cheers :)

[@SabbraCadabra11]

@@geekific Will do so, a huge thanks once again!

[@Talaria.School]

Hi thanks for effort It would have been good to add a repo to get the code. Anyway great effort!

[@geekific]

The link to the repo can be found in the description. Cheers!

[@Talaria.School]

@@geekific thanks sorry for my lack of look anyway great explanation

[@zukisamaliwa7668]

Can you add from where you left off by reading from a CSV file and calculate the shortest path please

[@geekific]

Hello! I'll be more than happy to enrich my videos with your suggestions :) Can you please detail what is it you are asking for exactly?

[@AvgABC561]

I can't use the toList() method on my Stream :/, do you know any solution to that?

[@geekific]

It was introduced in Java 16

[@manOfPlanetEarth]

1:11 "any sub-path B to D of the shortest path..." Not "any", but simply "sub-path B to D...", because there is only ONE sub-path for the shortest path.

[@geekific]

In this example, yes, but the sentence itself can be generalized on any graph! :)

[@manOfPlanetEarth]

@@geekific How can it be? You mean not strict minimum? Like a few shortest paths with the same length?

[@geekific]

@@manOfPlanetEarth I mean if you found the shortest path from node A in any graph to a node D in that same graph, then if node B is on that path, then the shortest path from B to D coincides with the path you previously found!

[@manOfPlanetEarth]

@@geekificYes:) That's right what I pointed at:) There's only one sub-path of any shortest path:) If B is not on the shortest path then that's another story.

[@manOfPlanetEarth]

5:20 Any reason you use Collections.singleton(source) instead of Set.of(source)?🤔

[@geekific]

In this example, no, both work fine :) But you just gave me an idea for a video :P Cheers!

[@manOfPlanetEarth]

@@geekific I LOVE your videos!!!!:)))) Will be looking forward for that video😊 [topic] I bet on the second because of the brevity:) ps. thank you for communicating in comments!

[@hankie5]

will it works in undirected graph?

[@geekific]

An undirected graph is basically a bi-directional directed graph!

[@hankie5]

@@geekific ooooh, yeah, thank you

[@hankie5]

@@geekific i thought, that will be an invifinity cycle

[@trollface1994]

Werrt ???

[@weihyac]

thank you