[Test]
public void PalindromeInTheBeginning()
{
    _sut.LongestPalindrome("babad").ShouldBe("bab");
}

[Test]
public void PalindromeInTheMiddle()
{
    _sut.LongestPalindrome("cbbd").ShouldBe("bb");
}

[Test]
public void PalindromeAtTheEnd()
{
    _sut.LongestPalindrome("asedad").ShouldBe("dad");
}