It's a neat solution, but it also seems like someone is trying to game StackExchange (and now Hacker News) to boost their rep with I really don't care for.
Live and learn.
If you had a difficult problem, didn't find a solution on stack overflow, but did figure it out before you had a chance to write up a question, put it up (with the answer) anyway. It might be useful to someone else.
This is the key thing that newcomers to Stack Overflow don't realize. Not understanding this distinction between a Q&A forum vs a Q&A archive is why people get so pissed at SO being quick to close off-topic and duplicate questions.
That's not exactly accurate with regards to the current options for voting to close a question. But the general reasoning here is that it's an anti-spam measure. It filters out low-effort questions (eg. homework questions) and forces you to be specific and concrete enough with your question for the question to be suitable for SO.
Simply describing the task and providing sample inputs and outputs tends to be too open-ended and often strays into the territory of asking for someone else to write all the code for you, rather than help you solve a specific problem with your code.
There's a huge difference.
Ideally, yes you're right.
> Can I answer my own question?
> Yes! Stack Exchange has always explicitly encouraged users to answer their own questions. If you have a question that you already know the answer to, and you would like to document that knowledge in public so that others (including yourself) can find it later, it's perfectly okay to ask and answer your own question on a Stack Exchange site.
It's not that one is late to the party. More like someone didn't know the parties were happening all the time, and finds out about them in retrospect when it comes up in conversation several years later.
it happened to me more than once to get stuck on something for a couple hours without a solution in sight, start typing the SO question, think of something and tada !