What does the // do in python and c++?

Answer 1

In python, the double forward slash is used when you want the result of a mathematical calculation as an integer and not as float e.g.

7/6 = 1.1666666666667

then
7//6 = 1 (it truncates the result)

BTW, that's python 3. Not sure about its function in C++.

Answer 2

In C++ it is used for comments.