new_contents: # Time:  O(n)
  # Space: O(n)
  
  class Solution(object):
      def kEmptySlots(self, flowers, k):
          """
          :type flowers: List[int]
          :type k: int
          :rtype: int
          """
          days = [0] * len(flowers)
          for i in xrange(len(flowers)):
              days[flowers[i]-1] = i
          result = float("inf")
          i, left, right = 0, 0, k+1
          while right < len(days):
              if days[i] < days[left] or days[i] <= days[right]:  
                  if i == right:
                      result = min(result, max(days[left], days[right]))
                  left, right = i, k+1+i;
              i += 1
          return -1 if result == float("inf") else result+1
          
  
subject: Create k-empty-slots.py