Tell me what the 3rd line is doing please.
int main(){
int *p = new int[3];
*p++=0; // What's this line doing?
delete p;
return 0;
}
1
votes
You should be more concerned about the line that follows that one.
- chris
What's it doing? It is invoking the dreaded undefined behavior. Prepare for a high risk of nasal demons.
- dmckee --- ex-moderator kitten
3 Answers
3
votes
*p++=0; means this:
- Write
sizeof(int)zero bytes to an address stored inp. - Increment the value of
pbysizeof(int).
In other words — you have incremented the pointer and what you then passing to delete is not the same as was returned by operator new[].
As @FredLarson has also mentioned, you have to use delete [] p; in order to delete an array.
Also, I'd recommend you read up on pointers, pointer arithmetics and pre-/post-increment. Pick a book from our Definitive C++ Book Guide and List.
1
votes
