Given the task definition and input, reply with output. In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.

One potential issue with these objects can be obviated with the tortoise-and-hare algorithm or Floyds circle-finding algorithm, which is a linear-time procedure for finding loops. The amortized runtime for most operations on these structures can be reduced by building an array on each container, or by building-up from one of these a multi-level parallel series of them; those are the techniques of unrolling and skip creation. If the ends of these are protected with self-referential containers called sentinels, they are not prone to cause addressing faults, which usually result from moving past the end. Uni-directional iterators were created to work with these data structures, which are commonly implemented as objects containing a value and a pointer to an object of the same kind. For ten points, name these data structures idealized as series of chained nodes.
Science