multiset-multicover

This package implements the Greedy Cover algorithm for multisets in C++ and exposes it to Python. Given a universe of elements U, and a family of subsets F = {S1, ..., Sn} of U, the set cover problem asks to find the smallest number of sets in F such that every element of U appears in at least one such set. This can be extended to a multicover problem, where we ask that every element be included at least k sets. This in turn, can be extended to accomodate multisets, where each element in Si also has a given multiplicity.

    The set cover problem is NP hard. The best known algorithm
    is a greedy approach that iteratively selects the set with the largest
    number of elements that have not been covered yet. This algorithm
    has a log(n)-approximation guarantee where n is the size of the largest set.
    The same guarantee also applies to the multicover problem, as well as the
    multiset multicover problem (n here corresponds to the size of the largest
    set, counting multiplicities).