[Solved] Dynamic arrays in C++

Question

I was trying to read input with a function and assign that to a dynamic array, but unfortunately it doesn’t seem to work and I don’t know why…

Please take a look at my code:
https://code.sololearn.com/c9PxmQMlG2ge/?ref=app

Answer 1

Maisu You have to pass a pointer (or a reference) to a function for change it inside a function thought its a pointer.
You want change dynarr (int*) from read function with args arr (int*).
You passing the dynarr value (null, in this case) that will be overwrited by new int n BUT locally in the read function. The origina dynarr will not change.
You can solve in different ways, using a pointer to pointer or, better, a reference to pointer.
Declare the arr argument of read as int *&arr (means a reference to pointer to int) and all will works because in read function you will use a reference to original pointer and not more a copy.

Answer 2

Passing the <arr> argument as reference seems to work ...

Line 4
void read( int n, int*& arr )

Answer 3

KrOW Thank you for the explanation !

Answer 4

ChillPill 🌶
Your help is needed here.
Could you help me out ?

Answer 5

Ipang Indeed, it works, thank you !

Answer 6

Maisu You are welcome

Answer 7

Quien me puede ayudar con este trabajo

Answer 8

Katie Andrade Esta pregunta ya ha sido respondida