Describe(Sample_Tests) {
  It(Test) {
    Assert::That(calculator(420, 0, 420), Equals("Invalid Input!"));
    Assert::That(calculator( 1, '+', 1), Equals("2"));
    Assert::That(calculator( 16, '+',9), Equals("25"));
    Assert::That(calculator( 1, '-',1), Equals("0"));
    Assert::That(calculator( 57,'-', 62), Equals("-5"));
    Assert::That(calculator(-10,'*',  10), Equals("-100"));
    Assert::That(calculator(-12,'*',  -13), Equals("156"));
    Assert::That(calculator( 2, '/',4), Equals("0"));
    Assert::That(calculator( 4, '/',2), Equals("2"));
    Assert::That(calculator( 1, '/',0), Equals("Invalid Input!"));
    Assert::That(calculator( 3, '%',5), Equals("3"));
    Assert::That(calculator( 5,'%', 3), Equals("2"));
    Assert::That(calculator(6, 69, 69), Equals("Invalid Input!"));
  }
};