UC Riverside

This paper describes a simple greedy δ-approximation algorithm for any covering problem whose objective function is submodular and non-decreasing, and whose feasible region can be expressed as the intersection of arbitrary (closed upwards) covering constraints, each of which constrains at most δ variables of the problem. (A simple example is Vertex Cover, with δ=2.) The algorithm generalizes previous approximation algorithms for fundamental covering problems and online paging and caching problems. © 2012 Springer Science+Business Media, LLC.