1

I am looking for a data structure to add, remove, get, and find on categories.

For example:

Books

  • Drama
  • Science fiction
  • Other

Sports

  • Cycling
  • Golf
  • Team Sports
    • Soccer
    • Football

etc.

I think about using tree from the C5 collection library for example, but it looks like it has only red-black trees. Any suggestions?

Peter Mortensen
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rabashani
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2 Answers2

5

You can just create a Category class that exposes a list of other Category instances.

public class Category
{
    public Category()
    {
        this.ChildCategories = new List<Category>();
    }

    public string Name { get; set; }

    public IList<Category> ChildCategories { get; private set; }
}
Mark Seemann
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  • this is start feeling like a tree to me... how do you put the next item? for example add soccer node as a child of team-sports node which is a child of Sports child... [Why implement this... when you can use a tree...] – rabashani Aug 25 '09 at 13:58
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    +1 I like your answer, but use a Dictionary instead of a List. – Brian Gideon Aug 25 '09 at 14:04
  • @rabashani: Create a new Category instance and give it the Name "Soccer", then add it to the ChildCategories of another Category instance with the Name "Team Sports", etc. – Mark Seemann Aug 25 '09 at 14:16
3

A tree would be a good approach, but I get the feeling you are thinking there is going to be a one-size-fits-all data structure that you could use and that is not really how I envision it. I concur with Mark's solution, but recommend a Dictionary instead of a List. That way you can lookup a Category and get its subcategories quickly.

Brian Gideon
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