Leetcode题解之 —— 对称二叉树

思路

参考上一题

题解

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/**
 * @param {TreeNode} root
 * @return {boolean}
 */
var isSymmetric = function (root) {
  if (!root) {
    return true;
  }

  return isSameNode(root.left, root.right) && isSameNode(root.right, root.left);
};

function isSameNode(left, right) {
  if (!left && !right) {
    return true;
  }
  else if (!left || !right) {
    return false;
  }
  else if (left.val === right.val) {
    return isSameNode(left.left, right.right) && isSameNode(right.right, left.left);
  }
  return false;
}