function L = digraph_arc_example_abcd ( )

%*****************************************************************************80
%
%% digraph_arc_example_abcd() returns the arc list for a 4-node example.
%
%  Licensing:
%
%    This code is distributed under the MIT license.
%
%  Modified:
%
%    17 April 2026
%
%  Author:
%
%    John Burkardt
%
%  Output:
%
%    integer L(5,2), the arc list.
%
  arc_num = 5;

  L = [ 1, 2, 3, 3, 4; ...
        2, 3, 1, 4, 1 ];

  return
end
