test_EdgeWeightedDirectedCycle.py

#/usr/bin/env python
# TBD: Finish Python port

#*****************************************************************************
 #  Compilation:  javac EdgeWeightedDirectedCycle.java
 #  Execution:    java EdgeWeightedDirectedCycle V E F
 #  Dependencies: EdgeWeightedDigraph.java DirectedEdge.java Stack.java
 #
 #  Finds a directed cycle in an edge-weighted digraph.
 #  Runs in O(E + V) time.
 #
 #
 #*****************************************************************************/

import sys

def main(prt=sys.stdout):
    """Unit tests the EdgeWeightedDirectedCycle data type."""
    pass

  ## create random DAG with V vertices and E edges; then add F random edges
  #V = int(sys.argv[1])
  #E = int(sys.argv[2])
  #F = int(sys.argv[3])
  #EdgeWeightedDigraph G = new EdgeWeightedDigraph(V)
  #int[] vertices = new int[V]
  #for (int i = 0; i < V; i += 1)
  #    vertices[i] = i
  #StdRandom.shuffle(vertices)
  #for (int i = 0; i < E; i += 1):
  #    v, w
  #    do:
  #        v = StdRandom.uniform(V)
  #        w = StdRandom.uniform(V)
  #    } while (v >= w)
  #    double weight = StdRandom.uniform()
  #    G.addEdge(new DirectedEdge(v, w, weight))

  ## add F extra edges
  #for (int i = 0; i < F; i += 1):
  #    v = StdRandom.uniform(V)
  #    w = StdRandom.uniform(V)
  #    double weight = StdRandom.uniform(0.0, 1.0)
  #    G.addEdge(new DirectedEdge(v, w, weight))

  #prt.write(G)

  ## find a directed cycle
  #EdgeWeightedDirectedCycle finder = new EdgeWeightedDirectedCycle(G)
  #if finder.hasCycle()):
  #    StdOut.print("Cycle: ")
  #    for (DirectedEdge e : finder.cycle()):
  #        StdOut.print(e + " ")
  #    prt.write()

  ## or give topologial sort
  #else:
  #    prt.write("No directed cycle")

if __name__ == '__main__':
    main()