public int compare(Station s1, Station s2) {
		if(s1.getPheromoneLevel() == s2.getPheromoneLevel()){
            return 0;
        } else if(s1.getPheromoneLevel() > s2.getPheromoneLevel()) {
            return -1;
        } else if(s1.getPheromoneLevel() < s2.getPheromoneLevel()) {
            return 1;
        }else{
        	return 0;
        }
	}