Re: A basic question about linked list

On Jul 18, 5:56 pm, glen herrmannsfeldt <g...@xxxxxxxxxxxxxxxx> wrote:
veda wrote:
I want to know the correct procedure for deallocating memory that gets
allocated during creation of a linked list (I am using CVF).

(snip)

type curve
type(face_1d):: facet
type(curve), pointer::next
end type curve
type(curve), pointer:: head
type(curve), pointer::tail
type(curve), pointer::ptr_temp

(snip)

Later in the code, I want to re-define the curve identified by
"head" (e.g. all together different set of segments). What do I need
to do to deallocate memory correctly for the previously defined curve
before starting to define the new curve?

If is usual to pointer assign NULL() to the next pointer of
the last element in the list, which usually means you don't need
a tail pointer. In any case, you go down the list, saving the
next pointer in a temporary pointer, deallocating the current
element, and then copying the temporary to the current pointer.

Maybe something like:

do while(associated(head))
ptr_temp => head%next
deallocate(head)
head => ptr_temp
enddo
head => null()

If the list isn't terminated with a null pointer, you could use

do while(.not.associated(head,tail))

but null termination is better.

-- glen

Thanks. That is exactly what I needed.

.