```
class Solution(object):
def kEmptySlots(self, flowers, k):
"""
:type flowers: List[int]
:type k: int
:rtype: int
"""
days = [0]*len(flowers)
for day,flower in enumerate(flowers):
days[flower-1] = day
left = 0
right = k + 1
res = None
while right < len(days):
for i in range(left+1, right):
if days[i] < days[left] or days[i] < days[right]:
left = i
right = i + k + 1
break
else:
temp = max(days[left], days[right])+1
res = min(temp, res) if res else temp
left = right
right = left + k + 1
return res if res else -1
```