message: Update delete-columns-to-make-sorted.py
diff: # Time: O(n * l)
  # Space: O(1)
  +class Solution(object):
  + def minDeletionSize(self, A):
  + """
  + :type A: List[str]
  + :rtype: int
  + """
  + result = 0
  + for c in xrange(len(A[0])):
  + for r in xrange(1, len(A)):
  + if A[r-1][c] > A[r][c]:
  + result += 1
  + break
  + return result
  +
  +
  +# Time: O(n * l)
  +# Space: O(n)
  import itertools
  -class Solution(object):
  +class Solution2(object):
  def minDeletionSize(self, A):
  """
  :type A: List[str]
  