public void CalcFactorial_IsInputplus_ReturnAnswer()
        {
            var method = new MethodFac();

            int result = method.CalcFactorial(5);

            Assert.AreEqual(result, 120);
        }
        public void CalcFactorial_IsInputMinus_ReturnOne()
        {
            var method = new MethodFac();

            int result = method.CalcFactorial(-1);

            Assert.AreEqual(result, 0);
        }