private void CompareLengths(IThreeDVector vector1, IThreeDVector vector2) { var result = ""; switch (vector1.Compare(vector2)) { case -1: result = "vector1 < vector2"; break; case 0: result = "vector1 = vector2"; break; case 1: result = "vector1 > vector2"; break; } Console.Write($"Compare their lengths: {result}"); Console.WriteLine(); }