Quick Sort Algorithm (Tutorial 3) Decision 1 EDEXCEL A-Level

[HEGARTYMATHS]

Wow! What a compliment. Delighted to have helped.

[sanuhara]

wow.. tried hours of figuring out quick sorting on the internet, then i found this video..
thanks a lot for the share.

[kishanparmar]

Correct me if I'm wrong but at 12:17, the second row from red says 3, 10, 12, 16, etc... however, I think it should be 10, 3, 12, 16... bcs in your notes, it said to write down all items less than the pivot, but "keeping their order" and since 10 comes before 3, shouldn't that come first?

[AliTheTourist]

Got my D1 exam in 3 hours. Thanks Mr Hegarty!

[matthewgrammatico]

Thank you so much for uploading this! This has really cleared up some of the questions i was having. Will definitely be watching way more of your videos!
Thanks!

[pinkyjt]

I thought this was a brilliant video!I will definitely watch ALL of your D1 videos before my exam on Friday! Thankyou so much :)

[saheedo.shittu]

After pivoting 12, 10 was meant to come before 3

[FluteMaster]

Thanks for your amazing vid!

But a quick question, at 12:18, I thought that in the second row, it should have been:
10 (3) (12) But you selected the 3 first?

I'm a little confused as I thought you said to include numbers as they came? Could you please clarify this for me?

Thanks for spending the time to do these vids!

[MsSweetescape]

I found hope, that I may pass D1 ! THANK YOU !!

[Osisioma]

Good tutorial. However, check at 13.17, in the pivot, i got 17: 12, 33: 3, 16, 20: 10, 23: and 21, 29.

[davidhayes]

Still pretty good. I kind of like the chilled low(ish) tech approach.

[rangershot]

Hey thanks a lot for making these videos, very helpful and great explanations, however if you do see this could you answer  my questions about this ? 
In the video, on the first practice question your answers 2nd line shows the numbers as 3, 10, then 12 however from the order above you would have put it 10, 3, 12 as 10 was the first number lower than 12 in the sequence, not 3. I'm sorry if this seems pedantic i'm just curious as this was the answer I got to the question and wondered why it varied. Please if anyone who sees this could possibly solve my dilemma I would vastly appreciate it. 

[mtthwgff]

Thanks for the tuturial, what did you use to record? It looks like you're writing by hand.

[sookritimishra]

that was really helpful... too good (Y)

[usmanalam]

Message received. Subscribed immediately :D

[zinvob]

It will work, but it will not be the same as the algorithm. The algorithm uses as few data "flips" as possible. If it would use it this way, you would have to do extra store in memory or extra flips every turn. Since this should show how the actual algorithm work, you need to show the left and right pointer, and how they flip correctly.

that feeling when
free youtube tutorials are better than $2000 a year colledge lecturers

[NattapongPUN]

I don't quite understand your practice Q1. At second lines, If given i and j pointer are left side and right side, Why didn't swap between pair of 21<->3 and 23<->12?

[zinvob]

This description is wrong. You have a pointer at the top and bottom for the flip. You don't just fill in all smaller values on the left and bigger on the right. The order should be as the algorithm will trigger them while trimming down the left and right pointer. And that would be 21 8 13 23 29 42 24 39 28.

[cazld_]

if you're taking the aqa exam tomorrow, ignore this video as the specification is different. The pivot is always at the start of each list, not in the middle.