Java | Leetcode Java题解之第515题在每个树行中找最大值

题目：

题解：

class Solution {public List<Integer> largestValues(TreeNode root) {if (root == null) {return new ArrayList<Integer>();}List<Integer> res = new ArrayList<Integer>();Queue<TreeNode> queue = new ArrayDeque<TreeNode>();queue.offer(root);while (!queue.isEmpty()) {int len = queue.size();int maxVal = Integer.MIN_VALUE;while (len > 0) {len--;TreeNode t = queue.poll();maxVal = Math.max(maxVal, t.val);if (t.left != null) {queue.offer(t.left);}if (t.right != null) {queue.offer(t.right);}}res.add(maxVal);}return res;}
}