public void findPath(Node startNode, Node targetNode)
            throws HeapFullException, HeapEmptyException {
        Heap<Node> openSet = new Heap<>(width * height); // this where we make use of our heaps
        Heap<Node> closedSet = new Heap<>(width * height);
        startNode.gCost = 0;
        startNode.hCost = getDistance(startNode, targetNode);
        openSet.add(startNode);

        while (!openSet.isEmpty()) {

            Node current = openSet.removeFirst();
            ArrayList<Node> neighbours = getNeighbours(current);

            for (Node node : neighbours) {
                node.parent = current;
            }

            for (Node node : neighbours) {
                if (node.equals(targetNode)) {
                    return;
                }
                node.gCost = current.gCost + getDistance(current, node);
                node.hCost = getDistance(node, targetNode);

                if (!openSet.contains(node) && openSet.peekTop().getFCost() < node.getFCost()) {
                    openSet.add(node);
                }
            }
            closedSet.add(current);
        }

}