Exact cover

Exact cover is a concept from combinatorial mathematics and is particularly well-known in the context of the Donald Knuth's Algorithm X, which is used to solve the Exact Cover Problem. The problem can be described as follows: Given a set \( S \) and a collection of subsets of \( S \), the goal is to find a selection of these subsets such that every element of \( S \) is contained in exactly one of the selected subsets.