- var isSymmetric = function (root) {
- if (root == null) {
- return true;
- }
- //左中右顺序递归二叉树
- var nums = [];
- search(nums, root, 1);
- //判断是否对称
- var i = 0, j = nums.length - 1;
- while (i < j) {
- if (nums[i] != nums[j]) {
- return false;
- }
- i++;
- j--;
- }
- return true;
- };
- /**
- * 按照左中右顺序递归二叉树,输出至数组nums中
- * @param nums 输出
- * @param n 节点
- * @param k 层次
- */
- function search(nums, n, k) {
- //左边
- if (n.left != null) {
- search(nums, n.left, k + 1);
- }
- //节点值,层次
- nums.push(n.val + ',' + k);
- //右边
- if (n.right != null) {
- search(nums, n.right, k + 1);
- }
-
}
来自 <http://www.planetb.ca/projects/syntaxHighlighter/popup.php>