ToUnorderedPairs[g] constructs a list of unordered pairs representing the edges of graph . Each edge, directed or undirected, results in a pair in which the smaller vertex appears first.
To use ToUnorderedPairs, you first need to load the Combinatorica Package using Needs["Combinatorica`"].
An option called Type that takes on values All or Simple can be used, with All being the default value. Type->Simple ignores multiple edges and self-loops in .
