private void CalculateBalance()
{
IsBalanced = true;
TotalWeight = Weight;
if (Childs.Any())
{
foreach (var c in Childs)
{
c.CalculateBalance();
}
// Disc is balanced if all childs have exactly the same weight, ie 1/nth of their total weight
var w = Childs.Select(c => c.TotalWeight).Sum();
TotalWeight += w;
IsBalanced = w % Childs.Length == 0 && Childs.All(c => c.TotalWeight == w / Childs.Length);
}
}