public boolean canPlaceFlowers(List<Boolean> flowerbed, int numberToPlace)

 

/*
    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 booleans), return if a given number of 
    new flowers can be planted in it without violating the no-adjacent-flowers rule.
    */

    public boolean canPlaceFlowers(List<Boolean> flowerbed, int numberToPlace) {
        this.hashCode();
        if(flowerbed == null || flowerbed.isEmpty()){
            throw new IllegalArgumentException("bed is empty");
        }

        if(numberToPlace==0)
            return true;

        if(flowerbed.size()==1){
            return !flowerbed.get(0) && numberToPlace<=1;
        }

        int counter = 0;

        for(int i=0; i< flowerbed.size(); i++){
            if(!flowerbed.get(i)){
                if((i==0 && !flowerbed.get(i+1)) 
                || (i==flowerbed.size()-1 && !flowerbed.get(i-1)) 
                || (!flowerbed.get(i+1) && !flowerbed.get(i-1)) ){
                    //place the flower
                    flowerbed.set(i, true);
                    counter++;
                    if(counter==numberToPlace)
                        return true;
                }
            }
        }    

        return false;
    }

　

public class Solution {
    public boolean canPlaceFlowers(int[] flowerbed, int n) {
        int count = 0;
        for(int i = 0; i < flowerbed.length && count < n; i++) {
            if(flowerbed[i] == 0) {
	     //get next and prev flower bed slot values. If i lies at the ends the next and prev are considered as 0. 
               int next = (i == flowerbed.length - 1) ? 0 : flowerbed[i + 1]; 
               int prev = (i == 0) ? 0 : flowerbed[i - 1];
               if(next == 0 && prev == 0) {
                   flowerbed[i] = 1;
                   count++;
               }
            }
        }
        
        return count == n;
    }
}