Time complexity: Best and Worst cases | Quick Sort | Appliedcourse

Chapter Name: Quick Sort

[bibhuprasadsubudhi]

this ia what we students call a osm techer .love this session .thank you so much sir .

[nikhilgautam]

Best video for understanding the time complexity of quick sort algorithm.😎👌👌

[frazebean]

You're a legend man. I wish you all the best in your teaching journey cos you're gifted in it.

[rohithberavelli]

perfectly done by quick sort with your video.thanks for your explanation

[debaratighatak]

What an amazing explanation sir! Thank you :)

[achronicstudent]

I have question about 4:21 about drawing recursion tree. I always draw them like for each node, calculating the work done in this node. (as shown in Introduction to Algorithms 4th Leiserson Stein Rivest Cormen MIT Press p. 96) using this approach the recursion tree drawn should be n ---> cn, n-1--->c(n-1), n-2 ---> c(n-2), ... 1 ---> 1 but you draw it slightly different. I guess both approach gives the correct results for the example in p. 96 but i am not sure. Can you explain it a bit further?

[giantpanda]

when you analyze the worst case for quicksort, x is the smallest element as you said. so the n1 from Partitioning should be all bigger than x. But you wrote the symptom of <= x.
Just a minor mistake. ..
thank you for sharing this great video.

[prasannasasne]

at 11.46 you have mentioned the depth of the tree i.e log n to the base (10/9). can you please explain how you are calculating this depth?

[naniscompass]

What is the name for this teaching tool (colour pens)?

[sayantaniguha]

So,
Almost Best case is average case ?

[jagannathanvijaylakshmi]

Can u tell me which software is being used? I mean how to write with mouse.. sir..are u using any digital pen or something?

[rafiqn]

Bayya how to convert head recursion to tail recursion (tail call optimisation) please make video on it...

[uberboy]

You cannot say that Quick Sort's time complexity is Big-oh of nlogn because it's not. Big-oh represent it's worst case and the worst case time complexity of quick sort is O(n²). To represent the average case you should use Big-Omega which is another symbol: Ω(n log n). Try not to explain difficult subjects to other people if you are not sure about it, it's hard to understand it and it gets even harder if many people say different things about it.