public IColumn pollColumn() {
IColumn column = blockColumns.poll();
if (column == null) {
try {
if (getNextBlock()) column = blockColumns.poll();
} catch (IOException e) {
throw new RuntimeException(e);
}
}
return column;
}
public TreeNode buildTree(Deque<String> deque) {
String cur = deque.poll();
if (cur.equals(Null)) return null;
TreeNode root = new TreeNode(Integer.parseInt(cur));
root.left = buildTree(deque);
root.right = buildTree(deque);
return root;
}
public int[] maxSlidingWindow(int[] nums, int k) {
int n = nums.length;
if (n == 0) return new int[0];
PriorityQueue<Integer> pq = new PriorityQueue<>(k, Collections.reverseOrder());
Deque<Integer> queue = new ArrayDeque<>();
for (int i = 0; i < k; ++i) {
add(pq, queue, nums[i]);
}
if (n == k) return new int[] {pq.poll().intValue()};
int[] max = new int[n - k + 1];
int idx = 0;
for (int i = k; i < n; ++i) {
max[idx++] = pq.peek().intValue();
pq.remove(queue.poll());
add(pq, queue, nums[i]);
}
max[idx] = pq.peek().intValue();
return max;
}
public List<List<Integer>> levelOrder(TreeNode root) {
List<List<Integer>> ret = new ArrayList<>();
if (root != null) {
Deque<TreeNode> queue = new ArrayDeque<>();
queue.offer(root);
while (!queue.isEmpty()) {
List<Integer> row = new ArrayList<>();
int levelcount = queue.size();
for (int i = 0; i < levelcount; i++) {
TreeNode tn = queue.poll();
if (tn.left != null) {
queue.offer(tn.left);
}
if (tn.right != null) {
queue.offer(tn.right);
}
row.add(tn.val);
}
ret.add(row);
}
}
return ret;
}
public int[] maxSlidingWindow(int[] nums, int k) {
if (nums == null || k <= 0) return new int[0];
Deque<Integer> deque = new ArrayDeque<Integer>();
int n = nums.length;
int[] r = new int[n - k + 1];
int ri = 0;
for (int i = 0; i < n; i++) {
while (!deque.isEmpty() && deque.peek() < i - k + 1) {
deque.poll();
}
while (!deque.isEmpty() && nums[i] > nums[deque.peekLast()]) {
deque.pollLast();
}
deque.offer(i);
if (i >= k - 1) r[ri++] = nums[deque.peek()];
}
return r;
}
