Arrays in c++?

Question

Just a random question about arrays in c++
So every array must have it's size declared right?
What do we do if we don't know what the size will be?
I came from JS so I'm used to arrays just kinda being there and not needing it's size declared.

Answer 1

If the array will still have a fixed size, but you want to get the size from the user, for example, you can allocate it dynamically:
int arr* = new int[10]
This creates an array of ten elements, but it can be any size, essentially.
However, this only applies if you still know some kind of size.
If you need the array to shrink and grow, then you will want to use vectors. They are 'better' arrays and support most of the operations you might know from JS. Also, they don't neccessarily need to be constructed with a size. I'd highly suggest you to make yourself familiar with them if you want to advance in C++:
http://www.cplusplus.com/reference/vector/vector/

https://en.cppreference.com/w/cpp/container/vector

Answer 2

Thanks Shadow
I'll look into vectors.

Answer 3

I wish Somebody could give Daniel Cooper another QnA solution..
https://www.sololearn.com/post/38046/?ref=app

Answer 4

neptune rose that would cause a compiler error. It is illegal in C++ to declare an array of size 0.

Answer 5

Акбар Юсупов

Calviղ is most definitely a good person
y u insult?

Answer 6

Unacceptable comment

Answer 7

int arr[] = {};