message: Update spiral-matrix-iv.py
diff: @@ -16,7 +16,7 @@ class Solution(object):
  :type head: Optional[ListNode]
  :rtype: List[List[int]]
  """
  - directions = [[0, 1], [1, 0], [0, -1], [-1, 0]]
  + directions = [(0, 1), (1, 0), (0, -1), (-1, 0)]
  result = [[-1]*n for _ in xrange(m)]
  i = j = d = 0
  while head:
  