benburk

  [3, 3, 2, 2, 1, 1] -> [[3, 3], [2, 2], [1, 1]]

  [1, 1, 2, 3, 3, 2, 1, 1] -> [[1, 1, 2, 3, 3], [1, 2], [1, 2], [1]]