This doesn't just sound like you don't know specific things like the linked list loop problem. It sounds like you don't place much value in understanding more than whatever it takes to get your code to run. That doesn't make you a person who I would want to work with.
Its the bad interviewing methods of the industry that is killing my skills,
Originally I was top a class programmer. Then I had a break lasting several months (supposed yo be a temporal quit - due to family issues). Then I couldn't get in any more.
But I still kept up by developing great personal projects (a RT 3D photographic scanner- for example), Except that through the years, as I concentrated more on development, My theoretical rehearsing stop, that affected interviews. My coding skills remained top class at first until i'm forced to work outside the industry 9 hours a day, 5/6 days a week (in a retail, restaurant - find it boring, not my calling), and now, after some few years of that , even my programming skills (and analysis skills) is now starting to get extremely rusty.
Its a chain effect that I wouldn't wish on my enemy
Yes, now i realise the solution was extremely simple, but i was attending to the forum during breaks in my long shift, was tired, lacked patience... if I'd known my judgement would be affected that much i would have waited for my day-off