605. Can Place Flowers

You have a long flowerbed in which some of the plots are planted, and some are not. However, flowers cannot be planted in adjacent plots.

Given an integer array flowerbed containing 0's and 1's, where 0 means empty and 1 means not empty, and an integer n, return true if n new flowers can be planted in the flowerbed without violating the no-adjacent-flowers rule and false otherwise.

Example 1:

Input: flowerbed = [1,0,0,0,1], n = 1
Output: true

Example 2:

Input: flowerbed = [1,0,0,0,1], n = 2
Output: false

Constraints:

• 1 <= flowerbed.length <= 2 * 104

• flowerbed[i] is 0 or 1.

• There are no two adjacent flowers in flowerbed.

• 0 <= n <= flowerbed.length

分析：满足左中右都是0就可以放

```python3
class Solution:
    def canPlaceFlowers(self, flowerbed: List[int], n: int) -> bool:
        avail_slots = 0
        for i in range(len(flowerbed)):
            if flowerbed[i] == 0 and (i == 0 or flowerbed[i-1] == 0) and (i == len(flowerbed)-1 or flowerbed[i+1] == 0):
                avail_slots += 1
                flowerbed[i] = 1
                if avail_slots >= n: #提早退出
                    return True
        return avail_slots >= n

```