Quick sort in 4 minutes

Step by step instructions showing how to run quick sort.

Sources:

[WhisperingWalnuts]

This is great video! but, I feel the algo provided in the end is not the same as the way he was explaining.. I went ahead and wrote my code for it same way he explained:
```
class Solution:
def sortArray(self, nums: List[int]) -> List[int]:

def quicksort(nums, lo, hi):
if lo < hi:
partition_resting_point = partition(nums, lo, hi)
quicksort(nums, lo, partition_resting_point - 1)
quicksort(nums, partition_resting_point + 1, hi)

def partition(nums, lo, hi):
pivotIdx = random.randint(lo, hi)
nums[pivotIdx], nums[hi] = nums[hi], nums[pivotIdx]
pivot = nums[hi]

l_idx = lo
r_idx = hi-1
while l_idx <= r_idx:
if nums[l_idx] <= pivot:
l_idx+=1
elif nums[r_idx] >= pivot:
r_idx-=1
else:
nums[l_idx], nums[r_idx] = nums[r_idx], nums[l_idx]
l_idx+=1
r_idx-=1

nums[l_idx], nums[hi] = nums[hi], nums[l_idx]
return l_idx

quicksort(nums, 0, len(nums)-1)
return nums
```

[EchoVidsu]

With every new quick sort video, I watch, I get more recursively confused.

[jonahrivera]

Guy: "I think you understand the concept"

Me: No I don't

[SAMURAIch]

I feel so dumb when i don't understand this, but then i just scroll the comment section and realise that im not alone lol

[Charoula]

*screams in Ross voice* PIVOT! PIVOT! PIVOT!

[yufangjuan]

To ones without enough background knowledge, this video omits details of execution of each step. But to ones with, this is concise and covers sufficient key points of quick sort. Thanks a lot for your video sharing.

[LL-rnrn]

The psudocode is not intuitively reflecting the walkthrough

[theducksneezes]

How to get Confused in 4 minutes








then again, this was the best video about it so far

[fr]

This is great. The simple explanation and the especially simple pseudocode towards the end makes it easy to understand the core concept of the algorithm.

[LGNNorotic]

you should put the code next to all of the visual aids and highlight each line as its being done in the visual. thanks for the help with sorting!

[sachinpathy]

i put this at 1.5x and now i learnt quick sort 2.6667 minutes

[mehdibadaoui]

when i search for something on youtube and see one of your videos in the results i genuenly get excited

[dh]

These are some clean tutorials. Thank you for making this!

[Kleyguy]

I think I'm here for the fourth time now.

[okaydayy]

That is the exact! same Quick Sort Algorithm we have been thought. Really good! Thanks

[seltonmc]

Your short videos helped me a looot. Thank you so much!

[brianmartinez]

I watched several videos, including my school books, and I had no idea what they were saying with left to right and could not get the answers in the correct order because of that. I was able to understand after watching your video and it allowed me to get past my assignment. Thank you.

[wendyd.]

I study computer science, and once, I had an exam with a few sort algorithms in it. I didn't really study but about twenty minutes before the exam I watched your 2-4 minute videos on these sort algorithms and I passed the exam. Thank you for helping me.

[Crzynoob]

Psuedo code does not match demonstrated algorithm.

[MewPurPur]

Yess I finally understood it, having a clear mind the morning before the exam helped