What I really liked going through though are project euler and 4ever-clojure problems. It's subjective but I suspect it's because you don't need to read through paragraphs of text before starting to write a solution. It's the opposite, the small problems with clear goals leave you with more space for creativity and urge you to write more code in the end. I personally found the hours spent on such problems to be more productive.
Regarding the contents of the advertisement, for those who bother with leetcode, why? I've tried random easy, medium, and hard problems. They're either silly (why would they even be asking those questions? and phrased so awkwardly) or mostly things any recent grad can solve in 10-60 minutes if they spend some time thinking about it. And for professionals, I'd expect it to be similar unless you haven't had to do any algorithmic thinking for years.
Many of the problems end up having a "trick" that greatly simplifies it once you spend 1-5 minutes thinking. I just pulled it back up and a random medium problem took me under 5 minutes. The "trick" was that most of the problem statement can be discarded because it's superfluous, that took me about a minute to realize. Then I wrote up a solution in about a minute and missed an edge case, took me a couple minutes to figure out what I'd missed and finally have a correct submission.
And that's coming in cold, if I were expecting to solve leetcode problems today I probably wouldn't have missed that (common to a lot of the problems) edge case.
For hiring organizations, you'll learn nothing about me from this except that I've not forgotten my high school CS class from the 1990s, and definitely wouldn't tell you anything about what I learned in college or as a professional since then. And that high school was nothing special with STEM. It was just a random public high school in Nevada focused on arts and languages, not STEM at all. The STEM courses were mostly average, maybe slightly above compared to the area, but we did not compete well with schools that actually focused on STEM.
EDIT: The hard problems do draw from things I learned in college, and not HS. But I've yet to see an easy one that HS me could not have solved with some modest effort or a medium one that would take more than what I learned in HS and my first year of college.
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Further EDIT: Regarding the title, the submitter put this up a day ago (https://news.ycombinator.com/item?id=41530482) and got no traction. So they tried again with the editorialized title. Still not much traction.
