Question

I have the following class which recurs on itself to form a tree-like data structure:

public class chartObject
{
    public string name { get; set; }
    public int descendants { get; set; }
    public List<chartObject> children { get; set; }
}

For each object in the tree I would like to populate the descendant property with the amount objects that exist underneath it.

Example structure:

chartObject1 (descendants: 4)
└-chartObject2 (descendants: 0)
└-chartObject3 (descendants: 2)
└--chartObject4 (descendants: 1)
└---chartObject5 (descendants: 0)

What would be the most efficient way of doing this?

Answer 1

This works for me:

public void SetDescendants(chartObject current)
{
    foreach (var child in current.children)
    {
        SetDescendants(child);
    }
    current.descendants = current.children.Sum(x => 1 + x.descendants);
}

I tested with this code:

var co = new chartObject()
{
    name = "chartObject1",
    children = new List<chartObject>()
    {
        new chartObject()
        {
            name = "chartObject2",
            children = new List<chartObject>() { }
        },
        new chartObject()
        {
            name = "chartObject3",
            children = new List<chartObject>()
            {
                new chartObject()
                {
                    name = "chartObject4",
                    children = new List<chartObject>()
                    {
                        new chartObject()
                        {
                            name = "chartObject5",
                            children = new List<chartObject>() { }
                        }
                    }
                }
            }
        }
    }
};

And got this as the result: