//Marble fell in its hole private void FillTheHoleIfMarbleIsIn(Marble marble) { Hole marbleHole = Holes.First(h => h.Number == marble.Number); if (marbleHole.Position.Row == marble.Position.Row && marbleHole.Position.Column == marble.Position.Column) { marbleHole.IsFilled = true; marble.IsInHole = true; } }