We are simply evaluating how you APPROACH a problem with those constraints.
If given such a problem, you throw your hands up in the air, or give me a lecture about how such a problem does not occur in real life, or how it doesn't represent your best-self, that itself tells a lot about you.
My question, as I repeat in other comments is this : WHY do you feel stressed ? Delve into your psyche for just 1 minute and it will boil down to - fear of being judged as incompetent. All we are looking for is someone who can set aside this fear TEMPORARILY. You don't feel pressure if your mom throws you this problem, right ? Can you do the same even if a million people are watching, but just for 2 minutes ?
Even if we throw you a NP-Hard problem, can you objectively spend 2 minutes thinking about it, talking another 2 minutes about how you'd approach it, and then saying, 'This looks like it's beyond my skillset' - That clarity of thinking, mastery of fear, and blatant honesty is worth a hundred github apache open source projects.
People who can't do this lack the maturity to understand that in real-life, nobody really gives a damn about our achievements and failures except us (and very close relatives of course).