/**
* Returns the keys in the BST in level order (for debugging).
*
* @return the keys in the BST in level order traversal
*/
private Iterable<Point2D> levelOrder() {
Queue<Point2D> keys = new Queue<Point2D>();
Queue<Node> queue = new Queue<Node>();
queue.enqueue(root);
while (!queue.isEmpty()) {
Node x = queue.dequeue();
if (x == null) {
continue;
}
keys.enqueue(x.key);
queue.enqueue(x.left);
queue.enqueue(x.right);
}
return keys;
}
private ShortestPath findShortestPath(int v, int w) {
if (!isValid(v)) {
throw new java.lang.NullPointerException("Invalid v parameter");
}
if (!isValid(w)) {
throw new java.lang.NullPointerException("Ivalid w parameter");
}
Queue<Integer> q = new Queue<Integer>();
boolean[] marked = new boolean[G.V()];
int[] distTo = new int[G.V()];
q.enqueue(v);
q.enqueue(w);
marked[v] = true;
marked[w] = true;
distTo[v] = 0;
distTo[w] = 0;
while (!q.isEmpty()) {
int a = q.dequeue();
for (int b : G.adj(a)) {
if (marked[b]) {
int length = distTo[b] + distTo[a] + 1;
ShortestPath sp = new ShortestPath();
sp.ancestor = b;
sp.length = length;
return sp;
}
distTo[b] = distTo[a] + 1;
marked[b] = true;
q.enqueue(b);
}
}
return null;
}