C++ delete[] operator [duplicate]

Question

Is this the right way to use delete[] operator?

int* a=new int[size];
delete[] a;

If yes, Who (compiler or GC or whoever) will determine the size of the newly created array? and where will it store the array size?

Thanks

Answer 1

For each chunk of memory allocated, the memory allocator stores the size of the chunk (that's why it is inefficient to allocate many small blocks compared to one big one for example). When delete frees the memory, the allocator knows how large the memory chunk is the pointer points to.