Why pointer is not NULL after using delete in C++

Question

I wrote this and wondering why "deleted" isn't showing as output.

int *p=NULL;
p=new int(10);
cout<<*p<<endl;
delete p;
if(p==NULL)cout<<"deleted"<<endl;

Can Someone explain why it isn't printing after using delete and why delete isn't making the pointer NULL ?

Answer 1

It's because when you say delete p you're deleting a pointer to memory which completely erases the reference to the new memory you allocated. When you say if p==NULL you're checking to see if the pointer was set to null when in fact the memory that it was pointing to was de-allocated so the pointer isn't pointing to anything. Which doesn't mean the same as having it point to NULL in C++.