Visualization of Quick sort (HD)

An animated demonstration of sorting algorithms.

This video shows two comparison based sorting algorithms: Bubble sort and Quick sort.

The algorithms are demonstrated by robots sorting balls by hue. Comparison based sorting algorithms must make decisions based solely on pairwise comparison results. This is visualized by the robot's short-sightedness, which forces them to perform pairwise comparisons in a very pronounced manner.

The video culminates in a contest. Each algorithm is presented with an identical series of balls and they compete to see which finishes the sorting task faster. In addition to raw speed, the number of comparisons they perform is also measured.
Advanced viewers will notice bubble sort performs comparisons quicker than quick sort. This is because quick sort has to move around a lot between comparisons. Quick sort aims at reducing the number of comparisons, but in domains where movement is costly, it becomes inferior to other algorithms, which aim to reduce movement as well.

[BioHzrd]

I like how after it announces that quick sort won, it just lets bubble sort slowly and pitifully complete its sort.

[ninthpayloader]

Bubble sort is so short sighted he didn’t even see that he lost

[ziskador]

omg i felt so sorry for bubble sort robot at the end :(

[ImmacHn]

Bubble sort will always have a special place in my heart :')

[hendroyohanes]

The moral here is to never give up even when you lose

[razerage]

bubble sort be like "I hate my life"

[granceroblast]

This has to be the best educational video on sorting I have ever seen!

[brainboy]

I like that quicksort isn’t annoying bubble sort and letting him just do his thing. Such a nice guy

[TomTom-gyov]

Legend has it that the bubble sort robot is still sorting

[sharpnova]

bubble sort: what is my purpose?

me: to sort in O(n^2)

bubble sort: omg

[realeques]

so awesome, we spent  45 minutes in college for what we could have learned through this video

[moogyboy]

Those have got to be the cutest robots I've ever seen. Look at 'em sort!

[legendgames]

Making computers look cute while also teaching a great concept in a lot of web development? Win-win!
Also, noting how the computers are short-sighted is a very good way of describing how computers actually do operations.

[UntakenNick]

When I grow up I want to be a sorting robot..

[katlicks]

I never knew how Quick Sort managed to have confidence in it's placement without going to the ends first.
That cleared it up really easily.

[galzigler]

You should make a visualization for all existing sorting algorithm. Your videos are really helpful, and the best that could be find online to explain how the sorts work.

[kenji]

Great video. Kids nowadays have so much good resource

[udiprod]

Thanks! Currently I'm busy with two other videos (coming up soon), but I appreciate the interest in more sorting videos. I hope to get around to it soon.

[MinecraftLD]

I want to hug bubble robot, he deserves it.

[thatalbeeguy]

Youtube in 2012: Oh, look at him, he is learning algorithms! I should recommend it to him some time later.

Youtube in 2020: eah! This just the right time!