Find the Duplicate Number - Floyd's Cycle Detection - Leetcode 287 - Python

0:00 - Read the problem
2:32 - Drawing Explanation
14:31 - Coding Explanation

leetcode 287

#floyd #cycle #python
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[rajeshseptember]

That's right. Even Floyd wouldn't have resolved this problem in 30 minutes. It goes on to say that given the nature of such requirements in an interview, certain solutions are best memorized so that you could use them in a different situation or if the same problem comes up again.

[shelllu]

Your 1min introduction on this problem literally cracked up me :D Never think of saltiness can turn into such a fun intro. Will probably remember this problem and how to solve it for a long time :D Thanks for making this video!

[JihChiLee]

This is the best video of explanation of Floyd’s algorithm I have seen so far…

[epsilonator]

I absolutely love the fact that you code the solution right in front of us while explaining it, whereas other coding YouTubers just show their already written code which sometimes becomes difficult to understand. Thanks a ton for your awesome videos <3<3

[joeycopperson]

That proof explanation was very good.. Even other big channels have failed to do it so smooth. thanks

[leungcheng]

Thank you so much for the video of clear explaination!

For the graph starting from 2:32, I think the outgoing pointer from node 0 should point at node 1 first. And then node 1 will point to node 3.
Skipping the node that is pointed by 0 will struggle at the situation that element in 0 index is already the anwser.

At last, really thank you for creating great website needcode with good videos of the explaination of solution!!

[interviewprep]

This is the only explanation of Floyd's algorithm that I could understand... Thanks for this video...

[Alzmerch]

I believe the head node at 2:35 should be 1 and not 0.

1 --> 3 --> 2 <--> 4.

This may cause confusion for others, thought I'd point it out.

[akankshasharma]

GOAT explanation. Everyone advised me to just memorize the algorithm, you're the only person to explain it to me.

[unmeshchougule]

Kudos! No one explained the algorithm better than this, thank you so much

[RM-bgcd]

These are the kind of questions that piss me the fuck off. if you get this question in an interview and missed out on class it's GG

Thank you for your explanation as always though, this channel is a gold standard

[tanoybhowmick]

Difficult problem, hard to solve without prior experience on it. Thank you so much.

[bharathithal]

Great solution and explanation but there's a small mistake in the linked list diagram. The first element is actually 1 and not 0.
Great work, thanks a lot!

[anshaneja]

Your explanation was very clear, easily understandable. Thank you

[gelvkzd]

You know what when you said that it is very difficult to solve this in 30 mins even for the person who invented the algorithm made me relief. Thanks

[sulinPL]

Thanks for breaking this down! I managed to crack it in time and space O(n) by myself, but space O(1) was a head-scratcher. Gayle McDowell’s "2.8 Loop Detection" in Cracking the Coding Interview had me thinking I needed a secret decoder ring. Found it here, and now I can finally put away the flashcards!

[tinymurky]

I will cry if I got this question in intervew

[harpercfc_]

Very clean and understandable explanation. I would rewatch it for more times. Thank you for your great work!

[kevinwang]

11:30 In the proof, the fast pointer was equal to P + 2c - x, but isn't that assuming the fast pointer only loops over the cycle once?

[asdfasyakitori]

I like the fact that you disliked this problem