function A = digraph_adj_example_sauer ( )

%*****************************************************************************80
%
%% digraph_adj_example_sauer() returns the adjacency matrix for the Sauer example.
%
%  Discussion:
%
%    This matrix appears on page 564 of the reference.
%
%  Licensing:
%
%    This code is distributed under the MIT license.
%
%  Modified:
%
%    28 February 2020
%
%  Author:
%
%    John Burkardt
%
%  Reference:
%
%    Timothy Sauer,
%    Numerical Analysis,
%    Pearson, 2006,
%    ISBN: 0-321-26898-9,
%    LC: QA297.S348
%
%  Output:
%
%    integer A(15,15): the adjacency matrix.
%
  node_num = 15;

  A = zeros ( node_num, node_num );

  A(1,2) = 1;
  A(1,9) = 1;
  A(2,3) = 1;
  A(2,5) = 1;
  A(2,7) = 1;
  A(3,2) = 1;
  A(3,6) = 1;
  A(3,8) = 1;
  A(4,3) = 1;
  A(4,12) = 1;
  A(5,1) = 1;
  A(5,10) = 1;
  A(6,10) = 1;
  A(6,11) = 1;
  A(7,10) = 1;
  A(7,11) = 1;
  A(8,4) = 1;
  A(8,11) = 1;
  A(9,5) = 1;
  A(9,6) = 1;
  A(9,10) = 1;
  A(10,13) = 1;
  A(11,15) = 1;
  A(12,7) = 1;
  A(12,8) = 1;
  A(12,11) = 1;
  A(13,9) = 1;
  A(13,14) = 1;
  A(14,10) = 1;
  A(14,11) = 1;
  A(14,13) = 1;
  A(14,15) = 1;
  A(15,12) = 1;
  A(15,14) = 1;

  return
end

