func canPlaceFlowers(flowerbed []int, n int) bool {
	l := len(flowerbed)
	if l/2+1 < n {
		return false
	}
	for i := 0; i < l && n != 0; i++ {
		if flowerbed[i] == 1 {
			i++
		} else if i == l-1 || flowerbed[i+1] == 0 {
			flowerbed[i] = 1
			n--
			i++
		}
	}
	return n == 0
}