public double Distance(DoublePoint2D target) => Math.Sqrt(SquareDistance(target));
public double SquareDistance(DoublePoint2D target) => (Math.Pow(X - target.X, 2) + Math.Pow(Y - target.Y, 2));
public double Distance(DoublePoint2D target) => Math.Sqrt(SquareDistance(target));
public double SquareDistance(DoublePoint2D target) => (Math.Pow(X - target.X, 2) + Math.Pow(Y - target.Y, 2));