Finding two non-subsequent elements in array which sum is minimal

Question

Intro: As far as I could search, this question wasn\'t asked in SO yet.
This is an interview question.
I am not even specifically looking for a code sol

Answer 1

Find the four smallest and consider all possibilities among those four. The smallest is nonadjacent to at least one of the second, third, or fourth smallest; the only other possibility that could be better is the second and third smallest (assuming that they are nonadjacent).