public void IdentifyAllChildren()
{
foreach (var child in OrbitedBy)
{
child.IdentifyAllChildren();
}
Children = new HashSet <string>(OrbitedBy.Select(ob => ob.Name).Concat(OrbitedBy.SelectMany(ob => ob.Children)));
}
public int Part1(int depth) => depth + OrbitedBy.Sum(ob => ob.Part1(depth + 1));
public void AddOrbitedBy(Planet orbitedBy)
{
OrbitedBy.Add(orbitedBy);
orbitedBy.SetInOrbit(this);
}
