isReachable

	public static boolean isReachable(int id0, int id1, int d) {
		if(d == 0) return false;
		if(checkFriendship (id0,id1) == true) return true;
		for(int i = 0; i < currUsers; i++){
			if(checkFriendship(id0,i)==true){
				isReachable(i,id1,d-1);
			}
		}
		return false;
	}