Choosing data structures solution

[LOGICO]

A program needs to set and keep track of Vans wich are free and vans wich are occupied doing some delivery.
It's necessary to know the state of a van so we can show all the vans and what they are doing. It's also necessary that the program can show the list of those who are delivering.

A couple of options for the data structures to hold the information:

FIRST

* ListOfFreeVans
* ProductList
* Work = Van + ProductList
* ListOfWork = all the Vans and the products they are delivering

when a van goes deliver a product (or more) it is removed from the ListOfFreeVans and a Work object is created that uses that van and a List of Products.

PROS:
- almost direct display of Vans that are occupied (Works[i].getVan () )
CONS:
- To show all the vans it's necessary to loop the ListOfFreeVans and the ListOfWork getting the van from each work.
- It inserts and removes Vans from each list when they change their state

SECOND

* ListOfVans - all vans
This list has a field called DELIEVRING that's either null of a reference to a ProductList
* ProductList

Example

[Van Code][delivery]
[Van1][null]
[Van2][xxxx]

To show all vans we just loop the ListOfVans and show the van.
PROS:
- easy to display the full list
- doesn't need inserts and removes to swap lists, just logic to change the value of "delivery"
- ...
CONS:
- need to parse the full list to show the occupied ones.


Any comments on these and other solutions are welcome. Thanks.

[MrViggy]

Use both! Seriously, depending on the number of vans, you could use both types of data structures. Store smart pointers, that way you really only have one object referenced by both lists (and the smart pointer will take care of clean up).

One of the projects I recently worked on was set up similarly. We had to sets of data structures, containing pointers to the same objects. That way, depending on how we needed to traverse the data, it would be fast.

Viggy