I was reserarching about Convex hull and Graham Scan to implement it and It drew my attention that everyone has used stacks. So I wanted to ask why are the stacks used in the algoithm precisely, what's the benefit of using stacks?
In graham scan while constructing the hull there is a need of backtracking if the points do not form a left turn with the next considered points so previous points need to be reconsidered as valid points of hull hence we use stack to get them in order of last visited first for re-validation. Though is its not mandatory to use stack you can use a simple array as well to do the same.