< 0, 0, 0, 0, 1,-1;
  1,-1, 0, 0, 0, 0;
  0, 0, 1,-1, 0, 0;
  0, 0, 0, 0, 0, 0;
  0, 0,-1, 1, 0, 0;
  0, 0, 0, 0,-1, 1 >