Can Place Flowers

Question

Suppose 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 - they would compete for water and both would die.

Given a flowerbed (represented as an array containing 0 and 1, where 0 means empty and 1 means not empty), and a number n, return if n new flowers can be planted in it without violating the no-adjacent-flowers rule.

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

Note:

• The input array won't violate no-adjacent-flowers rule.
• The input array size is in the range of [1, 20000].
• n is a non-negative integer which won't exceed the input array size.

Tags

• Array

Thought

Traversal through the whole array.

Code

class Solution(object):
    def canPlaceFlowers(self, flowerbed, n):
        """
        :type flowerbed: List[int]
        :type n: int
        :rtype: bool
        """
        result = 0
        for i, num in enumerate(flowerbed):
            if num == 0:
                if (i == 0 or flowerbed[i-1] == 0) and (i == len(flowerbed) - 1 or flowerbed[i+1] == 0):
                        flowerbed[i] = 1
                        result += 1
        return result >= n