MakeDirected[g] constructs a directed graph from a given undirected graph by replacing each undirected edge in by two directed edges pointing in opposite directions.
The local options associated with edges are not inherited by the corresponding directed edges.
Calling the function with the tag All, as MakeDirected[g, All], ensures that local options associated with each edge are inherited by both corresponding directed edges.
, you first need to load the Combinatorica Package using 
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