#error caused by:#1:{} 没有考虑None输入#2:{1,2,2} 没有控制h和t#3:{4,-57,-57,#,67,67,#,#,-97,-97} 没有考虑负号,将s从str变成list,采用9999代表空数值: --------------------- 逐层进行对称性验证,出现不对称就结束: # Definition for a binary tree node # class TreeNode: # def __init__(self, x): # self.val…