Add C++ data structures

[larissalages]

Code should go inside data_structures/cpp (yeah, we don't have this folder yet, please create :) )
Any contribution is welcome!

[whoanuragverma]

Please assign me. I am willing to do this.

[sakshi-negi123]

I just created pr for 2 programs. Please merge. Should I link the issue?

[chiillax]

Could you please assign me for this task ?

[srajantiwari]

Okay, I'll be contributing DSU @larissalages or if there is requirement for any other Data Structure implementation in C++. Please do let me know.

[saiharsha-22]

@larissalages I would like to contribute Data Structures and algorithms in c++, can I?

[PriyanshuGangwar]

Please assign me for this task ! Thanks.

[Jeewantha-Madubashana]

Hi, I would like to work on this feature. Please assign it to me.

[neha07kumari]

Please assign me this issue. @larissalages