[
  [[0, 0], [0, 1], [0, 2], [0, 3]],
  [[1, 0], [1, 1], [1, 2], [1, 3]],
  [[2, 0], [2, 1], [2, 2], [2, 3]],
  [[3, 0], [3, 1], [3, 2], [3, 3]],
]