Question

In C++ how can I pass an array as a reference when I don’t know the size at compile time? So far, I found out that the only way to make it work is to use something like

const double( &numbers ) [size]

but it means that I need to know the size of the array at compile time, thus I cannot use it in an external function.

My questions are:

1. If I don’t pass an array as a ( const double( &numbers ) [length] ), because for example I don’t know its size, how do I make sure that it doesn’t get copied, but it is referenced?
2. If I pass an array like in the above example, ( double array[] ) is it referenced or is it copied?

Answer 1

In C++, you should use std::vector.

In C/C++, you can’t pass arrays as a copy. Arrays are always passed by reference.

EDIT

In C++, arrays passed by reference has different meaning. In both C and C++, arrays decay into a pointer to the first element of the array. Please check the comments below.