So you have a function that is supposed to do something ... on a modern CPU or how it would change if you instead pass an object by constant reference is a bit of a mystery to me.

although the function is manipulated in the user-defined function with different array name m[5], the original array marks is manipulated. C++ handles passing an array to a function in this way to ...

malloc/free works, but developers should use new/delete instead as they are C++ constructs. Passing arrays to functions is not trivial with stack based array. Function must have an argument type that ...

Let’s look at the C++ code used to test the timing to walk through inheritance and virtual functions ... All it takes to implement that pass through the array is a loop making a virtual call ...

and then copying it to the internal array (1 copy), like the example above I want to construct an add() function which utilizes placement new so I don't incur the extra copy, but have no idea how.