[FEATURE REQUEST] Add B+ tree

[YanZZZZZZZZ]

What would you like to Propose?

I propose to add the algorithm for the B+ Tree

I would also add the appropriate tests for them.

Issue details

https://en.wikipedia.org/wiki/B%2B_tree

Additional Information

No response

[WilliamNian]

Hi, I want to work on this issue.
I can provide searching, adding and deleting functions apart from the tree.
can you assign this issue to me?

[YanZZZZZZZZ]

@tonyStark03 I don't think any of your basic functionality is implemented, it's just that the frameworks all return null. Your test contains too little range.

[YanZZZZZZZZ]

@WilliamNian I think your part is better.

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[github-actions]

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