Big O Notations

[@Akshay-cj3hq]

Most people don't like the speed, but I appreciate it. Thanks for making the tutorials fast and editing out time wasters.

[@derekbanas]

Thank you :) It is my way of being original

[@davetheroux4724]

H K☔nner

[@linusgo5177]

This guy is amazing! Explains things better than my lecturer ever can. Thanks so much for the clear and concise explanation

[@derekbanas]

+Linus Go Thank you for the nice compliment :)

[@driftyad]

+Linus Go Don't be mean to Thomas ;)

[@garrettburnett4145]

In a youtube community full of slow, unnecessary introductions, I appreciate the speed at which you jump into these lessons. Thank you so much and wish me luck on my data structures final!

[@derekbanas]

Garrett Burnett Thank you for the compliment :) Best of luck on your final!

[@clarebornstein263]

Your videos have completely saved my grades in my CS classes! I have some very nice, however confusing, professors and this really gave me the extra help I needed to actually understand what is going on in my problems sets. The speed at which you write the code and provide explanation is unheard of-- THANK YOU!

[@derekbanas]

Clare Bornstein Thank you for the nice compliments :) I'm very happy that I could help

[@TheKaveshan]

gonna get my degree cause of this guy....

[@derekbanas]

+DurbanCharo I'm very happy that I could help :)

[@viralshorts19766]

+Derek Banas ur awesome

[@docktordicking2852]

+DurbanCharo that also counts for me lawl

[@Wowthatsfail]

But you didn't

[@ahrarcorson6452]

@@Wowthatsfail stfu Derek's a national treasure!

[@derekbanas]

It is a great way to quickly see how well different algorithms scale. It also gives a tip on how the algorithm works. I'll cover hash tables, trees, graphs, etc. next. Each is best in specific situations

[@derekbanas]

I'm glad it helped :) I wasn't sure how deep I should have gotten into the math involved. I'm glad I covered enough to make it understandable

[@MCSGproject]

You're probably unaware of the time difference it takes most professors to explain this stuff compared to you.. And the clarity difference is unreal too.. Anybody in university who isn't aware of videos like this is at an extreme disadvantage.

[@derekbanas]

Thank you for the nice compliment :) I appreciate it

[@etiennedegaulle3817]

I second that. This was clear, accurate, and with concrete code examples. Thank you so much.

[@docktordicking2852]

So freaking treu. My proffesor talked about this last month, and i still did not get it. After this video its al clear...

[@SilverAlex92]

to be frank its not like this is some source of secret knowledge. I found this by searching big o notation in youtube XD but yea it was crystal clear

[@seventythreedavid]

My Professor is a big discreet mathematics kind of guy and he over complicates everything by not explaining it too much whilst expecting his students to extrapolate everything. Derek's videos have been a life saver for my advanced programming class with which I am currently struggling in.

[@derekbanas]

That is the best compliment I can get :) I'm very happy that I was able to help.

[@derekbanas]

It really depends on the organization. When I was an architect I was expected to do most everything except for the writing of the code. Yes I made decisions normally on algorithms

[@derekbanas]

Ja obaviti moj najbolji to pokriti svaku temu koja se traži od mene. Drago mi je da ti se sviđa. Neka Bog blagoslovi vas i vašu obitelj, kao i :)

[@ankitagarwal4914]

Excellent!!!.....I have done my complete engineering and after 5 years found such an outstanding way to explain this complex Big O Notation..Thank You

[@derekbanas]

Thank you :) I'm very happy i could help.

[@derekbanas]

Thank you :) I'm very happy that you enjoy the videos. I have many more videos coming.

[@derekbanas]

Thank you :) I'm glad you appreciate the editing because it takes forever to edit out all the pauses.

[@Ben-ki8ke]

The best explanation of Big-O Notation I've found. Thorough with clear examples given. Perfect!

[@derekbanas]

Thank you for the nice compliment :)

[@derekbanas]

I'm very happy if I'm able to help :) Some day I want to do a tutorial on how to pass common interview questions. I've covered many of them already though between the design patterns, OOD and refactoring tutorials

[@josikie]

thank you!!!

[@derekbanas]

Thank you for the compliment :) I'll hold a vote soon and see who wins. I would definitely like to cover C++

[@SecularSerenity]

O(log N) on the streets, O(N^3) in the sheets.

[@derekbanas]

+Austin Archer That's funny :)

[@SecularSerenity]

+Derek Banas yeah I'm actually pretty adamantly against Java, to be honest, but the concept applies universally and I know more than enough Java to know what's going on there. I really dig your videos. You explain concepts phenomenally well without condescending to your audience as if they've never seen a function before. A lot of it is just the fundamentals, but very useful nonetheless.

[@zackisser2451]

+Austin Archer The best explanation I ever saw of big oh notation , it's an intuituve introduction to get a feel about those notation , I've been introduced to those notations in a formal way , and understan them but now I feen them . thanx derek for your great work .

[@MwueLaFlaga]

+Austin Archer Why are you against Java?

[@rednax3788]

O(n^n) in the sheets

[@derekbanas]

Thank you for taking the time to write such a nice message. I can't believe anyone would even compare me to the Khan Academy, or NewBoston. That is quite an honor. You're very welcome :)

[@Oogam]

You are god. You just explained in 20 minutes what my textbook has failed to explain in an entire chapter! So much jargon and nonsense, when it should have been written in plain and simple English, like this was. Thankyou.

[@derekbanas]

Thank you for the nice compliment :) I do my best to eliminate the jargon.

[@jonalice]

Oh dear, you edit things so tight and it is so valuable every second of the video. Admire your wizardry on Java codes not just for the algorithm analysis, but the whole Java coding also! And you say to a reply for a comment that you enjoy making these? Gifted!!!

[@derekbanas]

Johnson Mathew Thank you for the nice compliment :) I'm very lucky to be able to do this.

[@RoanHidalgo]

Crystal clear tutorial on Big O Notation principles. I just needed a refresher of this algorithm analysis concept I learned in college; you turned about two weeks worth of frustration and confusion (in college) into 20 minutes worth of clarity and bliss (on KZbin)

[@derekbanas]

Thank you :) I'm happy that I could help.

[@derekbanas]

I'm very happy I was able to help :) I do my best to cover topics that most people ignore

[@LarsCabrera]

This guy made more sense of this than any professor, lab assistant or book I have ever read. Thank you!

[@derekbanas]

Thank you for the nice compliment :)

[@MrNelzya]

Subscribed. I love the speed and clarity. I came for Big O but I'm afraid I'm not going to be able to stop watching the rest of your videos. Really nice job.

[@derekbanas]

***** Thank you for the nice compliment :) Many more are coming.

[@blessthefate01]

Seriously, thank you sir. People like you make the internet a better place.

[@MrSupermanry]

You should come teach at UC Berkeley! The world needs more people like you that are smart and can articulate their knowledge in a way that others can actually tap in and think like them. Bravo! I can finally think of Big O Notation is a comprehensible manner. Thank you!

[@derekbanas]

Thank you :) I appreciate you taking the time. Yes I plan on covering advanced algorithms soon

[@lorenzowottrich467]

I'm 7 years later and this video helped me a lot!!! thanks! you're a great professor!

[@derekbanas]

You are very welcome :) Thank you for comparing me to professors at Berkeley. I always heard they were good. I'll do my best to keep helping for free

[@derekbanas]

Thank you :) I'm very lucky to have such nice people watching my videos

[@derekbanas]

I'm very happy I was able to clear it up for you. You're very welcome :)

[@derekbanas]

I edit out pauses so can cover more information in less time

[@derekbanas]

Thank you very much :) Everyone that watches my videos are very kind!

[@derekbanas]

I'd love to. C++ is my 2nd favorite language. I'm going to hold a vote soon on the next tutorial and it will be one of the options

[@derekbanas]

You're very welcome :) I'm glad you found it useful

[@ryanhaberle4884]

I appreciate all of your videos. I made a career change and went back to school for programming. Its one of the biggest challenges I have ever faced and Your videos have helped me with many topics that have come up. Thank you and please keep making them!

[@derekbanas]

I greatly appreciate you taking the time to tell me the videos have helped :) Congratulations on having the guts to make a career change! Believe me I know how hard that can be. I wish you all the best!

[@simontadesse5356]

Very helpful. I am glad i spent my 20 minute to follow this interesting tutorial. I am preparing for my C programming exam and i got key concepts about Big O notation. Very short intro...straight to the topic...Great video.

[@derekbanas]

Simon Tadesse Thank you for all the compliments :) Best of luck on your exam.

[@hrishimukherjee1157]

I'm in second year of Computer Science, and I've been watching videos for Computer Science since last year (related a lot to Discrete Structures, since I found it pretty complicated). But, I have to say that out of all the Khan Academy, New Boston and other such videos, NO ONE has explained this any better than you sir. I started watching your videos yesterday and I cannot explain how much I've learned and the stuff I already knew has become more clear. Please keep doing what you're doing!

[@123japanuser]

Pozdrav Dragi trener, To je jedan važan pojam. Iskrene zahvaljujući vama. Propušteni na zlato kao put bio drugačiji od uobičajenog. Nema problema. Najpredaniji učenik kaže Bog vas blagoslovio.

[@derekbanas]

C++ is awesome. I guess I haven't covered it only because I thought so many other people had. You guys ultimately decide on everything I do :)

[@derekbanas]

Thank you very much :) I try to do my best. I'm very happy that you enjoyed it

[@derekbanas]

I'll cover that asap. Thank you for the request

[@derekbanas]

You're welcome :) I'm glad it helped. I could have covered the math, but I figured it would be best to avoid it

[@derekbanas]

I'm not planning on covering them at this time. I've been getting requests for android, so I'll cover all the basic algorithms and data structures, but save mathematical analysis and discrete mathematics for a later date. I'm planning on teaching math topics in the future using video tutorials plus android games that make the learning process more fun and interesting. I haven't perfected that style yet. Everything in the future will combine videos with apps that reenforce the topic

[@derekbanas]

Thank you :) I have covered stacks and queues in my algorithm tutorials.Threads are in my java tutorial. I hope they help

[@humwishdom]

this is the best explanation of big O I have ever seen, lectures, text book, online resources in comparison, thanks

[@kckunal123]

This is by far THE BEST tutorial on Big-O notations I have seen on youtube ! Thanks to you Sir, my basic concepts on Algorithms are now ROCK SOLID ! :) Cheers !

[@derekbanas]

It works this way Math.random() * Max_Number + Min_Number Works out to numbers between 10 and 1000

[@MrEr1992]

FUCKING HELL MAN. better explained than 3 uni lecturers with PHD and +10 years experience in teaching. keep it up

[@ezatullahahmadi]

So I am studying Computer Science at King's. The lecturer spends 3 hours bullshitting about Big O notation, and here you are making everything clear in 20 min. Salute! I wish you could be our lecturer!

[@derekbanas]

+naseep habib Thank you for the compliment :) I'm happy I cleared it up.

[@suspiciousm]

Re-watching this video after many years, and its still the best refresher there is!

[@derekbanas]

Thank you very much :) I'm happy you find it useful

[@derekbanas]

Thank you for taking the time to say they are helping :) I very much appreciate that

[@eamonnca1]

This is pretty brilliant! I'm applying for jobs at Google, I guess I'd need to be as fluent and fast in cranking out the algorithms as you are.

[@derekbanas]

Eamonn I'm happy I could help :) Google has the best. Best of luck to you.

[@michaelhammond6770]

Eamonn qwt

[@dr6770]

Hey did you end up getting a ob at google? I have an interview soon and I'm trying to prep the best I can. Any advice? I'm going through CS fundamentals again to prep for the tech interview I have coming soon, it's been a while since I went through terminology since college.

[@hlulanibaloyi5503]

ff

[@dr6770]

@Suraj Narayanasamy Goo luck. I decided not to finish the process and went with another company. Google's interview process is too stressful for a job that most don't stay at for too long. I just needed an entry level job lol

[@prayagshah5098]

I've seen many tutorial's of yours, you've helped me more than anyone else to understand the concepts so easily, great job derek :)

[@derekbanas]

Prayag Shah Thank you for the nice compliment :) Many more videos are coming.

[@Calm_Energy]

I really appreciate the real code examples to better visualize how Big O notation is useful

[@derekbanas]

I'm happy it helped :)

[@alitariq7726]

How you sum up what we are trying to do in first few minutes is absolutely beautiful. Thank you!

[@derekbanas]

Thank you very much :)

[@derekbanas]

I'm very happy to hear that. You're very welcome :)

[@derekbanas]

I'm very happy that my explanation helped :) your very welcome

[@rickywilli]

Wow. That was by far the best, most clear explanation of this I've seen. The fact that you also use code, giving such a great visual backup is so helpful. Thank you for making this :))

[@derekbanas]

Thank you for the nice compliment :)

[@nikyabodigital]

ElementArray. Fabulous way of saying Elementary.

[@derekbanas]

Thank you :) I got a bunch of requests for this, so I figured I'd make it

[@derekbanas]

You're very welcome :) Im very happy I was able to help

[@ashwinmurali4345]

These tutorials are so precious that I sometimes feel bad I’m watching them for free. Thank you so much for everything you do Derek!

[@derekbanas]

Thank you for the compliment :) It is my pleasure to help

[@mauroroldan1315]

this video have 9 years old and is still so good, good job men

[@derekbanas]

Thank you very much :)

[@Truthiness231]

That aside: great explanation of O. I really didn't fully get the whole meaning of what it was (much less O(log N) or O(log N log)) until now. Very much appreciated.

[@kevinparsley8364]

Definitely do c++. One way I get understanding is to hear different people explain the same thing. So, even if someone else has covered the same thing, you would contribute to a better understanding with your explanation. Besides you have a cleaner delivery than most anyone else anyway.

[@danielsw]

Awesome! I have oral exam in algorithms and data structures tomorrow! great timing, thanks!

[@iGrendizer]

Thanks Derek, I was studying and learning Big O and you came and saved my life :P

[@MichaelBernardo]

Awesome, I learned more about Big O Notations in 20 minutes than I ever did in a term in university.

[@derekbanas]

I'm happy I could help :)

[@RonnetClaw]

I watched your python tutorial not too long ago and was inspired to take a regular course on it (thought that it was perhaps inadequate to learn it off youtube videos). So last week, I enrolled in a private class and earlier today as part of weekend assignments, my tutor sent me a mail with some links on it and BOOM GUESS WHAT - I'm back to DEREK BANAS videos again! If you are learning how to code, there's none better than good sir, Derek.

[@derekbanas]

Thank you for the nice compliment :) I'm amazed that so many professors are showing my tutorials!

[@nithingowda8350]

All the tech tutorial are to be played at 1.5x speed, this person is the only one where you gotta slow down the speed to 0.75x. Such efficient and short videos, just like his code.

[@derekbanas]

Thank you :) I get bored watching slow tutorials, which is why I'm the fast KZbin tutorial guy

[@nithingowda8350]

@@derekbanas Me too sir! Thank you for the tutorials!!

[@jmab0909]

Thank you so much! :) Two lecturers and a lot of reading and this is the first time this has made any sense to me at all.

[@planetmuman]

Great video. I am brushing up on my Big O knowledge in preparation for an interview with Google this week. Thanks for this video. I will add that I noticed a small bug in the very last example @ 20:16... You wrote 'testAlgo4.quickSort(0, testAlgo2.itemsInArray)'. I would presume you meant to write 'testAlgo4.quickSort(0, testAlgo4.itemsInArray)' which would run through all items in testAlgo4...

[@temphemp9251]

+planetmuman did you get the job??

[@maliciousinferno]

These guys below are right. You just revised with me everything I needed to revise, for upcoming interviews, in 20 minutes. Perfecto! Subscribing!

[@derekbanas]

maliciousinferno9999 Thank you :) I'm very happy I could help.

[@derekbanas]

Thank you :) I'm very happy that I was able to help!

[@pierregoldstein]

Thank you Banas, I wish we had more people like you.

[@bitsinmyblood]

Amazing how quickly you tear through this. Good instructional video, thanks!

[@derekbanas]

Christian Gentry Thank you :) I'm glad it helped

[@derekbanas]

Thank you :) I'm very happy to be able to clear that up. Thank you for taking a look at my videos

[@firebird208]

Well hello internet!!!! Finally one of my Comp Sci classes referenced one of your lectures! I've been watching your tuts for the past two years trying to get this degree. Nice to see i'm learning in the right place. lolol

[@derekbanas]

That's Great! Tell your professor I said thank you. You can't imagine how cool it would be for me to actually see a professor referencing one of my videos :)

[@derekbanas]

Sorry about that :( Little errors slip in every once in a while. I'm glad you liked it aside from that :)

[@derekbanas]

Thank you :) I do my best to pack as much information into each video as possible.

[@derekbanas]

You're very welcome :) Thank you for the compliment

[@UmarKhan-zl2jm]

At 4:45 It isn't order of 1 O(1). It should be called O(2) because there are two operations being performed 1) Assignment of newItem to items[itemsInArray++]. i.e items[itemsInArray++]=newItem. 2) The variable 'itemsInArray' getting increamented. i.e itemsInArray=itemsInArray+1

[@siomarapantarotto]

Would it be O(2)? YES but In Big O notation you drop all the coefficients. O(2), O(3), O(4).... becomes O(1). Attention: Even if there is a controlling variable, an algorithm can be O(1) if the variable has no impact on runtime.

[@allenvanco4169]

Mr. Banas why I can read the code and I can understand every things you say and I know must the syntax and tools for too many programming language, but even that I can't write even small program , I spent three years just self taught syntax . thanks

[@derekbanas]

You have to come up with little projects on your own and copy and paste as needed. Maybe take one of my example programs and then use all the same tools, but have them perform completely different solutions. It takes practice.

[@piyushalbert]

You are GOD of Tutorials.. Making learning much easier and fast.. Thanks from bottom of my heart. :)

[@bosniansoldier5305]

Just discovered you watching your Go Lang tutorial which is great, and this is promising as well. Love the pace, that is what makes you different - good fast pacing. Most videos are too slow, and I slowly lose interest. Better rewind than sleep :)

[@derekbanas]

+BosnianSoldier530 Thank you for the compliment :) I do my best to make original videos.

[@TheVerbalAxiom]

This man is EXTREMELY helpful. *Internet High 5's him*

[@derekbanas]

+Omar Moodie Thank you :) I'm glad it helped

[@derekbanas]

I'm very happy to be able to help :)

[@akhilthakur9803]

Derek Banas, you're da real MVP

[@derekbanas]

Akhil Singh Thank you for the compliment :) I do my best

[@akhilthakur9803]

Derek Banas Dude, you cover the toics at the pace they had to be covered for a tutorial.

[@derekbanas]

That's funny :D You guys really keep me on my toes. It always cracks me up when you guys catch every little error like the small "s" in simple.

[@gamingwithmeiguess96]

Of all the explanations i have looked up about this subject this video said and meant more than anything i have ever read. The code was a perfect way to make it clear.

[@derekbanas]

+Gaming With Me I Guess Thank you for the very nice compliment :)

[@surferadi96]

15:38 "We have to look at every single elevlvlllvlvvl"

[@jacoburger3456]

This is by far the best explanation I found on the internet! Thank you so much man.

[@derekbanas]

Jaco Burger Thank you :) I'm very happy that I could help

[@Majskolvenz]

I don't get the result of your O(n) test. A linear search with 100k elements took 4ms while 200k elements took 5ms and 300k elements took 18ms. Shouldn't the results have been 4ms, 8ms and 12ms if it's directly proportional?

[@jim8974]

That depends on if his arrays are worst-case which they are not because they are arrays with randomly generated numbers. A worst-case would be that you have to sort all of the elements. Big-O is worst-case time which I'm surprised he didn't mention that (I think). There is also big-Omega and big-Theta, but those aren't as important as big-O. My problem though is understanding the counting technique of counting the primitive operations to find f(n), which is the discrete mathematics that he left out,mainly when it comes to the for loops.

[@treyshaffer]

Big O notation is worst case scenario. Also, the JVM is complex, and it optimized the code during runtime based on patterns it finds.

[@yemil1]

Actually, in that particular example Derek was running a linear search in arrays that didn't have the item looking for. So, all 3 cases were worst cases. So, for linear search of 10k, 20k, 30k arrays i expect 4,5,12ms, not 4,5, 18. If we are to consider JVM efficiency, then i expect that to better then results of 3 case not make it worse. So the question still stands, why 18 not 12?

[@bksantiago1909]

yemil1 look for branch prediction. It might be the cause the latter part took 18s, branch prediction wasn't effecient since the array values are random.

[@kevinpacheco8169]

The worst case for searches are reversed-ordered. His was randomly ordered so you cannot strictly compare but it gives you insight to compute time. If he had bubblesorted in reverse and then did a linear* search it would be proportional as you have pointed out. As an exercise you should try it.

[@derekbanas]

Thank you very much for going through all that to show your appreciation. I very much appreciate the nice message :)

[@derekbanas]

I'm going to revisit algorithms soon. I'll make sure I do that

[@derekbanas]

Thank you :) I'm glad you found the video useful.

[@Famas54321]

Haha, I'm currently doing freshman year's course on Algorithms and Complexity, the professor does an awful job at explaining this concept as vividly as you do. Your videos are a great resource.

[@derekbanas]

Thank you for the compliment :) I'm happy to help

[@jwareleyUTube]

I had an interview question on this today ... and totally flunked it! Good explanation keep posting tutorials.