题解 | #对称的二叉树#

/* function TreeNode(x) {
    this.val = x;
    this.left = null;
    this.right = null;
} */
function isSymmetrical(pRoot)
{
  if(pRoot === null) return true
  function compare(node1, node2) {
      if(node1 === null && node2 === null) return true
      if(node1 === null || node2 === null) return false
      if(node1.val !== node2.val) return false
      return compare(node1.left, node2.right) && compare(node1.right, node2.left)
  }
  return compare(pRoot.left, pRoot.right)
}
module.exports = {
    isSymmetrical : isSymmetrical
};
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