Running Error - Robot is not stopping, forcing a stop

When I start the battlefield,my robot and other enemy are frozen. The println messages are not displayed in the robot console. But the command prompt shows the following error. I check that the cause of error is the addition of node in my queue (queue.add(n)). However, this line of code shall be fine i guess. So I would like to ask how to solve this error message? (this part of my program is for path finding using bfs)

Thank you.

• • • • • BATTLE 1, ROUND 1 *****

TURN 1: StudentRobot* (1) hard deadline exceeded - 532809us Err> Robot StudentRobot* (1) is not stopping. Forcing a stop. Err> Robot StudentRobot* (2) is not stopping. Forcing a stop. Raw score for 0.0 energy left: 0.0 Robots escaped: 0 Enemy destroyed: 0 Turns past after map reference time: 0 Turns move partially on black blocks: 0 Turns soft deadline excceed: 0 Average computation time per turn: 511706 Max turn computation time: 532809 Total bad events counted: 0 SCORE: 0.0

private boolean pathFinding_BFS(Node start, Node end){ LinkedList<Node> queue = new LinkedList<Node>(); queue.add(start); start.setMarked(); while (!queue.isEmpty()){ Node temp = (Node)queue.poll(); System.out.println("first node:" + temp.getPointInPath().getX() + " y " + temp.getPointInPath().getY()); if (temp.equals(end)){ temp.setPrevNodeInPath(temp.getPrevNodeInPath()); return true; }else{ for (Node n : temp.getAdjacentNode()){ System.out.println("in node:" + n.getPointInPath().getX() + " y " + n.getPointInPath().getY()); if (!n.isMarked()){ n.setMarked(); n.setPrevNodeInPath(temp); System.out.println("test n"); queue.add(n); //problem here } } }

} return false; }

public List<Point> getShortestPath(Point start){ Node src = new Node(start); List<Point> path = new ArrayList<Point>(); for (int i=0;i<endup.size();i++){ Node destination = new Node(endup.get(i)); if (pathFinding_BFS(src, destination)){ while (destination.getPrevNodeInPath() != null){ destination = destination.getPrevNodeInPath(); path.add(destination.getPointInPath()); } Collections.reverse(path); return path; }

} return path; }