Add Breadth First Search and Depth First Search functions in one program using C++.

[MuditWadhwa]

Hi,I would like to contribute to your repository as a participant in Hacktoberfest 2021. Could you please allow me to work on this issue as well as contribute well commented code for both BFS and DFS functions(in a single program) for graphs in C++? Can you please add the label hacktoberfest as well?

[shubhamnag14]

Can I contribute to repo