%--------------------------------------------------------------%

%   A simple graph with arc costs                              %

%--------------------------------------------------------------%

                            %          1

                            %       ___|____

arc(1,2,50).                %      |        |

arc(1,3,40).                %      2        3

arc(2,4,10).                %     _|_      _|_

arc(2,5,40).                %    |   |    |   |

arc(3,6,50).                %    4   5    6   7

arc(3,7,60).                %    |___ ____|   |

arc(6,8,70).                %        |        |

arc(8,9,50).                %        8        |

arc(7,9,50).                %        |________|

arc(4,8,20).                %            |

% arc(9,2,0).               %            9