Leetcode 3333. Find the Original Typed String II | Group By + Prefix Sum + DP Solution Explained

In this video,
We solve Leetcode 3333: Find the Original Typed String II using Python. We walk through a clear and intuitive explanation using groupby and dynamic programming.

You’ll learn:
🔹 How the problem builds upon Leetcode 3330
🔹 Understanding the total number of ways to form original strings
🔹 Dynamic programming to subtract invalid combinations
🔹 Prefix sum optimization
🔹 Complete dry run and time complexity analysis

🧠 Difficulty: Medium to Hard
👨‍💻 Language: Python 3

📌 If you enjoyed the video, don’t forget to Like, Comment & Subscribe!
🧑‍🏫 Let me know what problem you want next!

#leetcode3333 #findoriginaltypedstring #dynamicprogramming #pythonleetcode #groupby #prefixsum #leetcodehard #leetcodeexplained

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[statlearntech]

Hey Guys,
I'm planning to go live and discuss more with you all. Will be sharing a post soon with the date and time. Stay tuned..😊

[mastermati]

Thank you for using meaningful names. So many people use this competetive style, and then nothing is understandable.

[StephenMuteti-qx]

Goooat! The intuition and code is exemplary sir
My blessings

[shubham]

Nice explanation bro👏. Keep it up! You gained a new subscriber 😉

[KuntalPanda-zx]

what an explaination. i watched so many videos today until i discovered yours, and it is great👍

[uygar]

As soon as I saw that yesterday's puzzle was marked as Part 1, I looked up Part 2. And I immediately knew I couldn't solve it without your help. Thank you for this! DP is probably one of the hardest DSA concepts, would you consider making a generalized tutorial about it?

[gildedlynx]

12:02 Hi, can you please help me understand the logic of prefix sum array. If Alice has to type 1 character atleast, why are we considering empty strings?

[mohammedsuhail.s]

explanation was too good you are looks like neetcode kind of explanation but code little bit confusion keep posting bro

[charanganesh]

Thanks for the good explanation🙌. subscribed.

[ashishmishra]

Rather than creating random dsa than create seperate playlists of array, string, liked list, que & stack. I have been following striver dsa a2z. I had completed array step-1, 2
Now at string step-1. When creating playlist like array please start the theory first and logic behind that
Also in algorithm like two pointer, prefix sum, sliding window teach theory + intuition behind that then start the series on that can help entire statlearn comunity. My english is not good but I tried to convey my best. Thank you