import java.util.*;
import rpi.goldsd.graph.*;
import rpi.goldsd.container.*;

public class EulerTour
{
  public static void main( String args[] )
  {
    // Create Graph to represent transportation routes (i.e. digraph)
    Graph G = new Graph( "Transportation Routes" );

    // Create the Vertex objects
    Vertex Albany = new Vertex( "Albany" );
    Vertex Chicago = new Vertex( "Chicago" );
    Vertex Denver = new Vertex( "Denver" );
    Vertex Hartford = new Vertex( "Hartford" );
    Vertex LosAngeles = new Vertex( "Los Angeles" );
    Vertex Miami = new Vertex( "Miami" );
    Vertex Seattle = new Vertex( "Seattle" );

    // Add vertices to graph
    G.add( Albany );
    G.add( Chicago );
    G.add( Denver );
    G.add( Hartford );
    G.add( LosAngeles );
    G.add( Miami );
    G.add( Seattle );

    // Add directed edges to graph ...
    G.add( new DirectedEdge( Albany, Hartford ) );
    G.add( new DirectedEdge( Hartford, Chicago ) );
    G.add( new DirectedEdge( Hartford, Miami ) );
    G.add( new DirectedEdge( Chicago, Albany ) );
    G.add( new DirectedEdge( Chicago, Seattle ) );
    G.add( new DirectedEdge( Miami, Denver ) );
    G.add( new DirectedEdge( Miami, LosAngeles ) );
    G.add( new DirectedEdge( LosAngeles, Seattle ) );
    G.add( new DirectedEdge( Seattle, Denver ) );
    G.add( new DirectedEdge( Seattle, Miami ) );
    G.add( new DirectedEdge( Denver, Chicago ) );
    G.add( new DirectedEdge( Denver, Hartford ) );

    System.out.println( "Determining Euler Tour ..." );
    Path Euler = Algorithms.findEulerPath( Albany );
    if ( Euler != null )
    {
      System.out.println();
      System.out.println( Euler );
      System.out.println();

      if ( Euler.isReachable( Albany, LosAngeles ) )
        System.out.println( "Los Angeles is reachable from Albany." );

      if ( Euler.isReachable( Chicago, Hartford ) )
        System.out.println( "Hartford is reachable from Chicago." );

      System.out.println();

      Vertex London = new Vertex( "London" );
      G.add( London );
      G.add( new DirectedEdge( Albany, London ) );
      Euler.add( London );

      System.out.println( Euler );
      System.out.println();

      if ( Euler.isReachable( Seattle, London ) )
        System.out.println( "London is reachable from Seattle." );
      if ( ! Euler.isReachable( London, LosAngeles ) )
        System.out.println( "Los Angeles is not reachable from London." );
    }
  }


}