private void removeEdgeNodes(ArrayList<Coordinate> neighbours){
		for(int i = 0; i < neighbours.size(); i++){
			if(neighbours.get(i).getX() < 1
			|| neighbours.get(i).getY() < 1
			|| neighbours.get(i).getX() >= this.columns - 1
			|| neighbours.get(i).getY() >= this.rows - 1){
				neighbours.remove(i);
				i--;
			}
		}
	}