P78: Enumeration of all topological sortings of a directed graph

P78: Enumeration of all topological sortings of a directed graph

Input:

A directed graph $G =(V, E)$.

Output:

All topological sortings of $G$.

Complexity:

$O(|V| + |E|)$ time per sorting and $O(|V| + |E|)$ space.

Comment:

Reference:

[Knuth1974] (Bibtex)