public void ImNegOneToStringTest()
        {
            var token = new ComplexNumberResult(new Complex(0, -1));

            Assert.Equal("-i", token.ToString());
        }
        public void NegativeReToStringTest()
        {
            var token = new ComplexNumberResult(new Complex(-5.3, -2.12));

            Assert.Equal("-5.3-2.12i", token.ToString());
        }
        public void ZeroReToStringTest()
        {
            var token = new ComplexNumberResult(new Complex(0, 1.3));

            Assert.Equal("1.3i", token.ToString());
        }
        public void PositiveReToStringTest()
        {
            var token = new ComplexNumberResult(new Complex(5.3, 2.12));

            Assert.Equal("5.3+2.12i", token.ToString());
        }
        public void ZeroImToStringTest()
        {
            var token = new ComplexNumberResult(new Complex(5.3, 0));

            Assert.Equal("5.3", token.ToString());
        }