((test du papier RAIRO)
 2 3 4 0 -1 1
 (#[-1 0 0 0 1 0]
  #[0 -1 0 0 0 1]
  #[-2 -1 0 -1 2 1]
  #[2 1 0 1 -2 -1]
 )
 ()
)