📃: Add Linked list folder

[rafia-codes]

🟢 Title : Linked List
🟢 Programming language : C++
🟢 Objective : To touch slow-fast pointer concept along with some hard linked list problems
🟢 Summary :

We can add hard linked-list problems like reverse nodes in group of k

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✅ Details to Include When Taking the Issue:
Name : Hacktoberfest

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Happy Contributing! 🚀

Wishing you all the best on your open source journey😍.
Enjoy! 😎

[github-actions]

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[akshatj-05]

Hey i want to work on this could you please assign me this @rafia-codes

[sshekhar563]

I have created a Pull Request for adding the LinkedList folder in C++
It includes slow–fast pointer problems and several hard linked list challenges.

PR: #259

[github-actions]

Hello @rafia-codes! Your issue #234 has been successfully closed. ✅ Thank you for your contribution and helping us improve the project! If you have any more ideas or run into other issues, feel free to open a new one. Happy coding! 🚀