3 Types of Algorithms Every Programmer Needs to Know

It's my thought that every programmer should know these 3 types of algorithms. We actually go over 9 algorithms, what they are, how they work, real-world use cases, complete with code examples and explanations, but they fall under 3 categories, 3 types of algorithms you should know.
Sorting Algorithms - used to rearrange elements in a list or an array in a certain order. We discuss bubble sort, insertion sort, and merge sort.
Searching Algorithms - used to find or retrieve an element from a data structure, or to determine its existence and location in the dataset. We discuss linear search and binary search.
Graph Algorithms - used to solve problems related to graph theory, where data is represented as a collection of nodes (or vertices) connected by edges. You probably know these as trees. We discuss depth-first search (dfs), breadth-first search (bfs), Dijkstra's algorithm, and A* algorithm.
So, why are these algorithms you should you know? Because they form the foundation of efficient problem-solving in computer science. Their study not only enhances programming skills but also deepens analytical thinking. And they’re instrumental in optimizing software performance across a wide range of real-world applications. I hope you enjoy the video and learn a thing or two!
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Resources🔎
visualgo.net/en
www.toptal.com/developers/sor...
motioncanvas.io/
0:00 Why algorithms are important
1:35 Sorting Algorithms
5:44 Searching Algorithms
8:06 Graph Algorithms
12:29 Want more algorithm videos?
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[@mossabDiae]

The first video I watch on your channel, subscribed in 24 seconds because you started sharing value quickly without a long unnecessary intro.

[@rodoxsta]

Same here, but I subscribed after reading your comment!

[@FernandoSLima]

same

[@lukashuth9730]

Really nice and informative video while still being short without "unnecessary" information, i really liked it

[@yourma7055]

True

[@softcolly8753]

The only time I have needed to implement a sort algorithm in 21 years as a software developer was for interviews or university exams. Never needed a graph algorithm at all. These are all coded into libraries these days, though it's somewhat useful to understand them, understanding how to index a database properly (applying them) is far more useful.

[@gustavofagundes8994]

exactly

[@lukaszantoniak9046]

agree

[@drakkor1000]

amen

[@cbc700]

This was quite a nice video, especially the visuals. However, I agree with the sentiments of this thread. In three decades of coding, I've only had to implement a sort algorithm a handful of times. So rare in fact, I can't remember the last. Interesting to understand, but softcolly is right -- mostly seen in school and interviews. Your delivery is quite good -- going to check out your other vids.

[@joannehart9624]

Back in the late 70s when I started coding, we often needed to implement sorting algorithms into our code. Sometimes because the operating system did not have a system sort, and other times because the overhead of setting up the code to use the system sort made it easier to just code a sort into the program. Back then CPU and memory were at a premium, so we had rules such as if the program needed to search through a table of more than 100 entries, the program had to sort the table then preform a binary search. Fun times to look back on. That said, those approaches have stuck with me throughout my career and oft times helped me fix resource heavy applications that wouldn't finish within the time frame demanded by business. 🙂

[@JustDevInc]

This was very nicely done. The visuals and your commentary allowed me to understand the algorithms in ways that previous videos I’ve watched haven’t. They’d either be too basic of an overview to get what’s happening, or too code based without visual cues to help you understand. This was a perfect balance of simplicity and depth. Great work!

[@wille4986]

Your enthusiasm is infectious and reassuring - knowing someone else finds this all just as fascinating to dive into but presented with the quality as you do is a privilege to watch. Excellent video and I can't wait to see more! Thank you!

[@User.Joshua]

You certainly have a knack for explaining things in an easily digestible way. Thanks.

[@Kamuisakeu]

The quick and concise video with visual representation together with the code sample was right on the spot! Cheers to that and give us more!

[@aggumbi]

Wonderful video. As a scientist going through a programming journey, the way you show the visual and explain the code (with the highlights, etc...) is extremely helpful. More algorithm videos please! ❤

[@OGNord]

Dude this was gold. I’m currently on week 3 of CS50s course and I’m in love with C and programming so far. This is a very succinct explanation of each section! Thank you very much

[@thobiaslarsen8336]

Finally someone who is happy with C and doesn't cry 😃 Thank you for showing hope 🙏

[@zoeherriot]

@@thobiaslarsen8336 C rocks. Great language.

[@KaneryU]

idk why this comment made me so happy you go man! (or girl, lol)

[@thobiaslarsen8336]

Probably because there is a lot of negativity in the field right now, so its very refreshing to see something actually positive 😂

[@youMatterItDoesGetBetter]

C is cool.

[@BillyLongshot]

love the intro and general framing of this video: no glam dreams about becoming a software engineer but the actual nitty-gritty that actually makes you one

[@nitheeshraajar393]

Just want to let you know @7:35, you say Binary search is O(log n) but on the chart its pointing to O(n Log n). Very nice video 👍

[@jonarielmaravilla1503]

nlogn if data is unsorted i guess.

[@nitheeshraajar393]

​@@jonarielmaravilla1503 then yup nlogn to sort then logn to search

[@lagmaker]

​@@jonarielmaravilla1503 you cant use binary search on unsorted array

[@deraxelturrelkeign]

@@jonarielmaravilla1503 Binary search couldn't function (effectively) on unsorted data without sorting first. An unmodified Binary search will either find what its looking for in O(log(n)) like a normal binary search (the algorithm just happens to go the right direction), potentially falsely return -1 or I believe get stuck in an infinite loop.

[@murilourso]

He even said "for sorted arrays"

[@guitarman813]

One of the best videos I've seen for an introduction and basic explanation of important algorithms in computer science and programming. Awesome job! 👏

[@matias-dev]

Loved the video, straight to the point with the necessary information, i had this kind of algorithms shown to me in programming classes in college and i always dread how they were shown, sometimes people overcomplicate the initial step of a bigger problem (probably not in a badly intentioned manner), i think your video is a great way to get started on these topics!

[@GideonBryceTan-od4tq]

Well explained and condensed -- it's like crash course for algorithms. Great stuff!

[@wolfmansaw]

I've been coding for 55+ years and I'm so glad I found you today! Great stuff!!! Right into the code and no fluff! I think you define what it means to be a programmer!!!👍

[@Radio_N_Casa]

Truly enjoyed this, simple enough and yet leaves me wanting more. Well done

[@Andron4iKTV]

You made a mistake when show to us time complexity of binary search. You put finger emoji on O(n log n) insead of O (log n).

[@fknight]

Good catch! Thanks for pointing that out.

[@TT-hi7lp]

Was just about to comment about this

[@alexrubio9507]

​@@TT-hi7lphahaha same here

[@OGMann]

Oh yep. Everyone was.

[@techfixer1543]

Thank you! Your lucid explanations of these algos shows your in depth knowledge, and the accompanying graphs are fantastic and hit a home run in visually expressing the underlying concepts. And you keep the viewer engaged with your peppering of being flawlessly snarky. I had to rewatch the part on the Dijkstra's algorithm to let it sink into my ever evolving brain in "thinking and reasoning" mode. Fantisic vid overall!

[@ademromdhane1271]

Amazing how easy you can simplify this hard algorithms visually , good job i really like it

[@gregoryhost5188]

This was really amazing and great timing, I'm currently struggling with algorithms especially trying to figure out where and how exactly to use them.

[@flpflpflp]

Hey man, I've been a subscriber for a few years now. I think this is the content I liked the most. Keep up the great work!

[@ZiaCodes]

Hey hey, Your talking style is amazing! The way you explained the algorithms is fabulous! I love it!

[@typicallunchbox6934]

Awesome video, the quality and breakdown was great. Definitely going to be checking out more of your content :)

[@adnelfigueroa1227]

Awesome video! Loved your explanation and the fact that you incorporate funny comments. Exited to see more.

[@hunterlewis5566]

I'm fairly new to computer science and programming and I love this and would love to see more of this, you got my support and vote of confidence!

[@grassifuentes]

This is excellent. I took algorithm designs a year ago and this refreshed my memory by a lot and made me want to look into it for practicing again. Thank you!🙏🏽

[@alialibaba6672]

Hey Forest, great wor and marvelous graphical representation. Please continue

[@jynx0riZ0r]

Best explanation of dynamic programming ever. Thank you. ;-)

[@estevanprado2005]

Love this vid. nice guide on common and frequently used algorithms, definitely going to sub to your newsletter, thanks!

[@twisthard]

Nicely done and presented! A couple of these were not presented in my CS Data Structures and Algorithms course, and as such this was a great view into those. One algorithm I never really got the hang of was hash tables. Now you have me thinking about that again. Well done!

[@slayergaming5421]

Great video! I really like the visual depiction of Dijkstra's and A*.

[@semilife]

Hey Forrest, first video of yours I have watched. Great presentation style.

[@davidrichman2117]

Thank you, Forrest Knight! Just review for me, but I wanted to say that you have a wonderful down to earth way of presenting that I really appreciated. Keep up the good work!

[@christianmboula8923]

Superb content, excellent delivery! where were you when I was taking DS a few decades ago!

[@baky5372]

Whatever video editing software you are using is really cool. i loved watching the code being stepped trhough and then visually seeing what was occuring above it.

[@techsalesandmore3649]

never seen your channel before. Totally loving your animations!!!

[@rogueronin1010]

Make a new playlist for all algorithms in depth videos. Thanks for the bite size explanation.

[@escapist818]

Oh man I would love a deep dive video on hashing algorithms, your stuff is great!

[@ctaulelei]

You're explanation was better than anything I've ever heard! I love how you used Dynamic algorithm to explain the content 😜. First sub I've done in a while for this kind of content. Heading over to look at the rest of your stuff now. Thanks for your time and effort.

[@francisharrington3155]

Forrest, your videos are damn near perfect. I've watched 5 in a row and subscribed to your channel and the newsletter. Probably gonna pull the trigger on the notion studious next.

[@fknight]

I appreciate that! Hearing this really means a lot

[@ringringlord]

very straight to the point and zero clutter

[@surferbum618]

Thank you for making this. Yes please, more of these!

[@alivaliev5152]

Right when I needed it most, this gold! Keep on this!

[@Dwafford01]

I loved this video, I just want to say I finished my BSc it with programming specialisation in the end of 2020. Now for the first time I'm being treated as a developer by the company I'm working for. It's both exciting and nervous, but with videos like these I think I will be okay.

[@alexrubio9507]

Man I wanna say that you're so talented at making these videos. It is so clear that you love doing them. Please keep posting, you re a rockstar!

[@max_masterius]

It's so visual! I've got the motivation to look deeper. It's a long time after my university that I actually touched this topic.

[@DerNutzero]

i absolutely would appreciate another one on algorithms !! :)

[@rnzqt]

Great video, nice summaries. Thanks!

[@samiamgrnegsnhamnonftercan2ham]

Great vid, would love to see more on algorithms!

[@JasonWelch]

I love this video because it introduces people in a rather gentle way to these topics. I feel like I could write an entire book on my experience as a programmer at this point (not that I think anyone would care to read it). I've been coding for over 25 years since I was a teenager and got my first dev job at 20. Back then I was super arrogant until I began working with people far more skilled and experienced than me, and so I studied CS for several years. However, I think the problem back then wasn't so much a lack of willingness, but simply a lack of awareness. I didn't know what I didn't know. I remember struggling to understand BSP trees, and then it became obvious to me later why: I didn't even know about binary search! Videos such as this one are immensely valuable for those early on in their programming journey.

[@pingmetal]

Straight to the point! Great video!

[@spikeygoc]

Loved this video. More please. Passion and well explained 😁

[@user-ex8hb7hr3h]

Forest, just discovered your channel. Love your content and style.

[@mrskbbs]

Would love to see more stuff like that! Definitely subbing

[@j.p.bikes22]

Really good video, it’s a great summery of what I learned in collage. Will definitely rewatch this sometime in the future 👍

[@TampaCEO]

Outstanding video. I've been a professional developer for over 30 years and I have to say that this video is by far the best I've come across on KZbin. Here's why: 1. Outstanding graphics. That cannot be understated. 2. Outstanding explanations. 3. You get right to the point (no wasted conversation). Consider me a new subscriber (to add to your half million or so). Congratulations on the success of your channel.

[@krzysztofs3t532]

Wow man! I'm a mathematics major, working as a React developer and this video rekindled my pursuit for pure programing, not just learning another library! Thank you very much! Immediately sub!

[@DoNsMaK190]

thanks for all those efforts that made to make those graphic explanation

[@nasirusanigaladima]

I would love more of this, it's very interesting and informative

[@theodorewyatt3473]

I definitely like to see more algorithm videos you do them very well and explain things in similar terms. These things should help others as they go along their coding challenges when it comes to algorithms. I would says you should incorporate how code design patterns come into to play too.

[@alexaneals8194]

I enjoyed your presentation. I will say that many times insertion sort is used by quick sort once the array is partitioned into small portions like < 10 elements. Also, these are in memory sorts, so if your accessing the disks frequently then you may not want to use these algorithms. Same goes for binary search. I don’t know if you have already covered it, but knowing how to code parsers can be valuable. I have lost count of how many parsers, I have had to code in my professional career.

[@gypsyisking]

nice video! Would love more in depth and longer videos

[@vishnum4852]

Great videos. Liking this nitty gritty concepts which are not popular in yt We need more videos like this man..

[@adye88]

Thank you for this content. I really enjoyed it. pls keep putting out more!

[@omargoodman2999]

What about the "really bad" sorting algorithms? Like "Stalin Sort": Step through the list one item at a time and, if the item is out of order, delete it. This results in a sorted list at the end [may result in some lost data]. Or "Miracle Sort": Step through the list and check if the items are in sorted order. If they are, return the list of sorted items. If not, wait a designated amount of time, recur function to see if the list has miraculously become sorted. Continue recursion until a sorted list is found.

[@realkorgo]

Nice video! The hashing idea sounds interesting! 😊

[@cedrickmccallon]

Almost 20 years into the game and I wish my CS teachers would have explained these algorithms this well. Great video.

[@BetweenTheBorders]

I'll be honest, I almost didn't click on this video, bur I thought "you know, as a dangerous amateur, I should see what I should know." And I guess since I've implemented A* before, I'm not too far off the mark. Good to have some sort and search concepts in the toolbox for future research. Well presented!

[@zakuguriin4521]

I built an array sorting algorithm visualizer with some classmates in programming school for our Javascript Team project. Watching it sort huge arrays was so addicting and mesmerizing.

[@markpalma1761]

showing which part of the code the is being ran live with the animation makes learning this much easier

[@dondominic6999]

Really great video. It would be interesting to see a video on the Knapsack algorithm, and the boarder linear programming and optimization algorithms.

[@EagleHunt]

Make more videos like this. Informative content is what I’m here for

[@aaronmorgan4466]

Really great explanations, thank you. This highlights where I came unstuck in AoC '23 quite well :)

[@lalodominguez7121]

Thanksnfor sharing. This is a great help by visualizing the algorithms. Subscribed

[@ericajcruz]

Great video. More "boring" algorithm videos please! Thank you for posting this.

[@incognitiveincognito]

Wish you where my data structures proffesor, then I might not of had to retake the class so many times haha. Amazing video, can't wait to see your other stuff

[@hu5116]

Great video! Love that you covered the gamut, yet KISS!

[@aimansyahmi6571]

Please do more of these types of video!!

[@iceboxLP]

really nice video and a very good presentation. please consider making more videos as such

[@teddyfulk]

Going to study up on these, thanks!

[@TheDanielvenom]

I always think that I have one kind of sort. This video literally blows my mind. Good vid.

[@kanemetal]

I don't comment often...this was awesome Forrest! Keep 'em comin'!

[@cuerpoymentesaludables]

Great explanation, thank you. Subscribed

[@wyohman00]

I wish every creator on KZbin would watch your videos! To the point with no baloney. Thanks!

[@Nynxxx]

I would love for you to do more videos on this stuff as I am about to finish my Comp Sci degree, and I am currently struggling with algorithms. I have not been the best with math in the past, and I just feel like there is something about algorithms I am missing. It just isn't clicking. I understand what they are and what they do, but if I get asked a simple question about solving what time complexity something is, I completely fumble, and just don't even know where to start.

[@youMatterItDoesGetBetter]

Loveeee that you’re getting that degree. People talk down on degrees nowadays, but they really do get you in the door.

[@baky5372]

Please more algorithm videos! I liked and subscribed!!

[@BamboozledOrca]

This was so well done!

[@alejandrodiez5511]

This is really good bro, thank you

[@alfonzo6320]

Man this is a pretty good video! keep up the good work.👍

[@SN-ed7wi]

Excellent vid for all the reasons stated by others, well done. Too bad there are some who think the info is not practical today. The fundamentals you learn by coding even one of the efficient sorting algorithms will stay with you forever.

[@oussamabenberkane9779]

Great vid man! You told me to comment about this so I would like a "hashing algorithms" video please, thankyou 😌

[@joaquinpickelny8958]

I really hope you are making money off these videos (this is the first one I've seen), because every single cent would be well deserved. From the content itself to the visual examples and code, not to mention how easily you explain these concepts in a complete yet straightforward way. It took me maybe 13 seconds to subscribe.

[@fredrikzels2637]

Really interesting!! More of this.

[@LukeBrady]

Fantastic video. Subscribed!

[@FedorTroitsky]

Thank you for the video! Very concise and well made! Just wanted to point out that some of the characters were cut in the merge sort code fragment for example mid cannot be a middle of arr if you don't divide it with //2. I just tried to mentally follow all algorithms line by line and found out that some lines made no sense to me, (I'm also quite new to python syntax so was just checking myself).

[@alceguy]

Amazing. Keep up the good work!

[@miyagi6486]

keep this kinds of videos, entertaining and helpful

[@skilz8098]

When working with 3D Graphics and a Scene Graph Hierarchy for world object placements and collision detection systems, one of the more generalized and efficient data structures - algorithms is the BSP Trees and its variants. Binary Space Partitioning Trees are very powerful. Related to them are also the Quadtrees and Octrees. Another type of algorithm not mentioned here which is a bit different than your conventional sorting or searching algorithms is your transformation algorithms. I'm not necessarily referring to transformations as physical translations within basic kinematic physics such as horizontal - vertical translations, rotations, and scaling perse but more on the lines of transforming data or input singles from one domain to another. One of my favorite algorithms especially with in analysis is the Fast Fourier Transform and its inverse. A few other noteworthy algorithms are ODEs (Ordinary Differential Equation solvers), Integrators, regressions models (linear, quadratic, cubic, etc.) and Interpolations. Other than that, this is great video for everything you covered is right on point! We always have to consider both the time and space complexities of various algorithms, containers, and datasets knowing the various tradeoffs between them. The only other thing that would be missing from this video is how different containers and algorithms are affected by locality especially when considering cache coherency and perhaps branch predicting, page boundaries and alignment as they can very well affect the performance and efficiency of various algorithms.

[@amador1997]

Love your enthusiasm

[@explorster]

Thanks Frank. Great content 👌