CS 216 - Data Structures Homework #8

NOTE: This work is to be done in pairs. 

Topological Sort

Implement the topological sort programming contest problem of http://www.spoj.pl/problems/PFDEP/ with the following change: Output may be any topologically-sorted order.  This way, you can implement the text DFS traversal.  (For the problem as given, a "source-removal" algorithm would be necessary.)