[ [ 1,-1,-1, 1, 0, 0, 0, 0 ],
  [ 0, 0,-1, 1, 0, 1, 0, 0 ],
  [ 0, 0, 1,-1,-1, 0, 0, 0 ],
  [ 0, 0, 0, 0, 1,-1,-1,-1 ],
  [ 0, 0, 0, 0, 0, 0, 1, 0 ],
  [ 0, 0, 0, 0, 0, 0, 0, 1 ] ]