public void CalculatePropertyFee_ForBusiness(decimal price, int lengh, int width, decimal expected)
        {
            //Arrange
            var calculator = new FunctionProgrammingDemo();

            //Act
            var result = calculator.CalculatePropertyFee(price, lengh, width, calculator.CalculateForBusiness());

            //Assert
            Assert.Equal(expected, result);
        }
        public void AddTreeNumberTest()
        {
            //Arrange
            var demo = new FunctionProgrammingDemo();

            //Act
            var result1 = demo.AddThreeNumber()(1, 2, 3);
            var result2 = demo.AddThreeNumberCurring()(1);
            var result3 = result2(2);
            var result4 = result3(3);

            //Assert
            Assert.Equal(6, result1);
            Assert.Equal(6, result4);
        }