Is this faster?

I understood nothing, but guess it's clever)

This is a great way to practice Duration class methods. Very well done.

True best practices

Go to stack overflow if you want to actively be unhelpful.

why isn't that helping? is that still the information you're looking for or something else?
ask specific things. if you failed to google, then google better xd - include the language, avoid special characters

Īn Java (and many other programming languages), ^ denotes the boolean "exclusive or" or "xor" function. A xor B is equivalent to (A or B) and not (A and B), or in English "one or the other but not both".

0 ^ 0 == 0
0 ^ 1 == 1
1 ^ 0 == 1
1 ^ 1 == 0

I am wondering - what does '^' do in the second if statement? Does it work the same way like '&&'?

Mine was a lot like this, but I only defined isEven. I really should have commited xD

You are right. It should not raise an exception.
Luckily the tests don't contain invalid chars, so this solution passes.

How can this be the highest rated solution if it doesn't even ignore invalid chars?

"Keep it simple, stupid" is a mantra in software design, not actually calling anyone stupid. Also, you're replying to a comment which is over 2 years old...

you stupid! his solution is better than yours