I bomb on technical interviews the same way because my mind just freezes and can't get through even simple problems.
I had the same question you mention. "This is a problem a paper was written on, are you expecting me to derive a whole paper from first principles in half an hour, or are you expecting me to have seen it before? If it's the latter, why not let me Google, as I normally would?"
I feel that saying "I would solve this problem with <algorithm>" should be good enough, and if I'm asked to implement it, I should be able to copy paste the Wikipedia pseudocode and start converting.
I had the same question you mention. "This is a problem a paper was written on, are you expecting me to derive a whole paper from first principles in half an hour, or are you expecting me to have seen it before? If it's the latter, why not let me Google, as I normally would?"
I feel that saying "I would solve this problem with <algorithm>" should be good enough, and if I'm asked to implement it, I should be able to copy paste the Wikipedia pseudocode and start converting.