Dijkstra's algorithm in 3 minutes

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

[@rahulsonwalkar3663]

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

[@ObradovacPower]

SO TRUE HAHAHA!!!!! lmao

[@BiancaDianaT]

On point ._.

[@haoranlou155]

气死我了，被抓包了

[@JHmuniz1]

30 min*

[@phylmath]

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

[@LevyaFox]

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

[@coolbildzlego]

same lol

[@christopherrondeau9829]

Fucking same, fuck uni teachers

[@burstfireno1617]

same here :D

[@ilyasviel731]

same here :D@@burstfireno1617

[@adamnavratil2350]

That's weird honestly

[@ThisClark]

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

[@MichaelSambol]

James Clark Thanks, James. More coming soon.

[@psibarpsi]

An implication of Parkinson's Law.

[@sumitsapkota3792]

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

[@ROFEL]

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

[@ramimxss]

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

[@SuperBhavanishankar]

@@ramimxss s

[@loot6]

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

[@blazingsniper1239]

​@@loot6 so true

[@Tombalino]

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

[@emresarac2100]

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]

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

[@Omenemperor2]

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

[@harshsason3725]

@@BossKing1243 Yup exactly.

[@adriangjonca680]

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]

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

[@AB-ld1rp]

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]

worked for me

[@VandamePlays]

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]

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]

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]

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

[@pkgamma]

13 hours is a lot of time dude

[@shadowagent3]

nice now 3 years later i got an exam tomorrow. Hope i do really well.

[@adamplayz-qf8ry]

Broo....

[@martinluther7791]

13 hrs. You're like a baby. Watch this S I X H O U R S

[@sankalpmahajan443]

Nice

[@rayryeng]

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!

[@z.m.4331]

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

[@prasp999]

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!!

[@JonathanRose24]

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

[@SuperBhavanishankar]

hope you got selected

[@BossKing1243]

Update?

[@tiannawrona9269]

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.

[@farzaadify]

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

[@ethandenson7182]

do you mean review?

[@pkgamma]

why tf do you have access to KZbin during exam

[@matejpersic6601]

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]

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!

[@antonhall2696]

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 :)

[@kevinqagish2287]

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

[@MichaelSambol]

Danke fürs zuschauen!

[@Majestic469]

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

[@E_D___]

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

[@Kaira_edits8]

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

[@MichaelSambol]

welcome! crush it

[@easyas-is]

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

[@d_asude]

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

[@nawdawg4300]

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

[@MyNguyen-ln1dv]

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

[@danielalvarez9404]

Dude, I love you

[@livea404life]

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

[@thealiens386]

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

[@mrsword6493]

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

[@godsepicgamer3825]

EVERYONE explains this so hard this REALLY helped me thank you

[@TheJunkieBox]

Short and sweet. We need more videos like this.

[@MYY-on5rk]

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]

exactly my thought

[@hassassinator8858]

It's meant to find the shortest distance to each node from A, not shortest distance in total.

[@li-pingho1441]

The best tutorial ever

[@davidwong666]

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

[@ogCharaLM]

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

[@epiclasersharks1866]

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

[@audiomac]

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

[@YouB3anz]

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

[@MidnightBloomDev]

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

[@adriangjonca680]

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

[@thanasulas08111994]

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]

thanasulas08111994 ***** Working on it now!

[@MichaelSambol]

kzbin.info/www/bejne/pZO6iZ2qnJV_bJY

[@matthewblom1620]

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

[@MichaelSambol]

💪🏼❤️

[@georgeoneal3641]

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]

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.

[@indianpublic4543]

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

[@theamici]

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]

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).

[@dirtworm979]

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

[@MichaelSambol]

Happens to the best of us 😴

[@SupunKandambige]

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]

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

[@ozancngz]

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

[@mr.paarthurnax2649]

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

[@24Ship]

you're an angel

[@skelswap]

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

[@kamadaichii]

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

[@tangdexian3323]

I really like your approach, concise and to the point

[@drewkelly3622]

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

[@yusram.6175]

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

[@Bred0nSch00lV2]

A nice condensed little video. Thank you.

[@creamsn3]

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

[@bunpun5135]

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

[@inigo1880]

Guess who's nearing the awful grade now :)

[@leonellbais1659]

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

[@ManhTran-ry9ux]

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

[@marcosangelmedina5845]

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.

[@hassassinator8858]

Well, it is his first language... 😂

[@elvischen6390]

I like these well-explained tutorials so much. If you don't mind, I would like to ask your permission to share these tutorials to the other website in China for the embarrassing reason that KZbin is blocked from accessing in China with translations. Of course, I will give sources of the original link. Appreciated.

[@jordancleeve7548]

Awesome video thanks!

[@JamesBrodski]

Great video! Thank you so much for making it.

[@lolejunior3168]

My g saving people life right now

[@lalwho]

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

[@aidan8465]

I can't believe I just found the Holy Grail of KZbin channel for CS students

[@MichaelSambol]

💪🏼❤️

[@rg5113]

1:15 Show the process of you updating the path at every vertex. Don't just say, oh we update it, and then magically show the numbers changing.

[@TFTAlecUchiha]

You are such a king

[@Alestrix76]

Except for the pseudocode you forgot to mention the need of storing the predecessor node as well. This becomes clear very quickly when one tries to actually apply the algorithm as explained here - one would have to somehow memorize through which path a certain cost was achieved, but "somehow memorizing" is not what an algorithm should require.

[@HuyPham-id7us]

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

[@MichaelSambol]

You're welcome, Huy! Thanks for watching.

[@andywei5518]

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

[@Siigrit]

Exam in 1 hour, thanks for this!

[@brandoncazares8452]

Thanks, Michael this video's very helpful.

[@chiminim424]

Bro u truly are the best keep up 🔥

[@faheemahmad3957]

Dear Sir Please do More videos and make them more simple and interactive and also add new Algos all of them!

[@axelmartinez1235]

Okay there is a bad misconception here. Select vertex w of which has smallest dist[w] among all unknown vertices. you do NOT base it off the edge, and you will always need to look at your chart to determine the next vertex.

[@pedroraimundodossantosneto5846]

Concise and straight to the point. Thanks =)

[@LioHmusic]

Exam saver!! Thanks

[@cantorbernoulli4407]

my man thanks for saving me time

[@AACVOMMIDHARANI]

Thank you soomuch yaar you made my day much better

[@kevinzhang7228]

Your videos are great!

[@sarveshpandey1125]

It's such a perfect explanation.

[@vado4003]

It was a bit hard to grasp this but we use a queue because we want to process a node by the fastest way we got to that node, i.e., if we could get to A with 5 and there is an option later to get there with 7, 5 is always preferred

[@gedeonandrasmusic]

Very great, thanks for your help!

[@zakyoung2374]

I have my exam in 30 minutes this is perfect

[@Yawneazy]

thank you so much for this! Life changing

[@theningdynasty]

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

[@houssemdhiab7337]

thank you dude for saving my life :D

[@404gloom]

i love when people dont make things harder than they need to be.

[@nemanjabosko]

I passed algoritm class because this man

[@MichaelSambol]

heck yeah

[@francoismeli9885]

Nice video. Please, just noticed a little typo : I believe the time complexity is O((|E| + |V|)log|V|) instead of O(|E| + |V|log|V|)

[@kaliferguson2232]

Very clear explanation. Thank you!

[@ognjensimic5042]

Hvala brate moj!

[@MichaelSambol]

💪🏼❤️

[@ogedaykhan9909]

so dijkstra algorithm is basically bruteforce

[@calebkrauter4027]

This is so good. Thanks!

[@jimkash7133]

a truly inspired work 10/10

[@digvijayandhorikar936]

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

[@Mobin92]

Why is nobody explaining how the final step works??? After calculating those numbers, how do we find the shortest path from them?

[@kautukraj]

Very helpful!

[@Brian-oo3pb]

hey, ever thought about doing a video like this on the A* algorithm?