public void DivByZeroTest()
        {
            StupidCalculator stupidCalculator = new StupidCalculator();
            int num1 = 6;
            int num2 = 0;

            Assert.ThrowsException <DivideByZeroException>(() => { var result = stupidCalculator.Div(num1, num2); });
        }
        public void MulTest()
        {
            StupidCalculator stupidCalculator = new StupidCalculator();
            int num1 = 1;
            int num2 = 5;

            Assert.AreEqual(num1 * num2, stupidCalculator.Mul(num1, num2));
        }
        public void DivTest()
        {
            StupidCalculator stupidCalculator = new StupidCalculator();
            int num1 = 6;
            int num2 = 2;

            Assert.AreEqual(num1 / num2, stupidCalculator.Div(num1, num2));
        }
        public void SubTest()
        {
            StupidCalculator stupidCalculator = new StupidCalculator();
            int num1 = 1;
            int num2 = 5;

            Assert.AreEqual(num1 - num2, stupidCalculator.Sub(num1, num2));
        }