Dynamically allocatable array

Question

I want to know the difference between

int *pia=new int[10];

and

int *pis=new int[10]();

In other words, I want to know what is in the pia when it is not initialized but has been allocated memory space.

Mike Seymour · Accepted Answer · 2014-09-04 12:24:11Z

3

The first specifies default initialisation; for simple types like int, this means there is no initialisation and they have unspecified values.

The second specifies value initialisation; for simple types like int, this means they are initialised with a value of zero.

answered Sep 4, 2014 at 12:24

Mike Seymour

256k30 gold badges467 silver badges658 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Does the newer uniform initialisation syntax int *pis=new int[10]{}; also work in this case?

@Niall: Yes, that also gives value initialisation.