P325: Enumeration of all topological sortings of an acyclic directed graph

P325: Enumeration of all topological sortings of an acyclic directed graph

Input:

An acyclic directed graph $G = (V, E)$.

Output:

All topological sortings of $G$.

Complexity:

$O(|V|N)$ total time and $O(|V||E|)$ space.

Comment:

$N$ is the number of solutions.

Reference:

[Avis1996] (Bibtex)