This question
https://leetcode.com/explore/learn/card/binary-search/135/template-iii/945/

is mentioned under template III of binary search learn card. But I cant think of a binary search solution.

Template III says both the neighbours of the mid element should be checked to decide whether to go left or right, the problem space is divided into 3 part after every iteration.

I dont understand why did they it put there. Please Explain this