17.树的子结构(python)

题目描述

输入两棵二叉树A，B，判断B是不是A的子结构。（ps：我们约定空树不是任意一个树的子结构）

 class Solution:
     def HasSubtree(self, pRoot1, pRoot2):
         # write code here
         if pRoot1==None or pRoot2==None:
             return False
         def getEqual(pRoot1,pRoot2):
             if pRoot2==None:
                 return True
             if pRoot1==None:
                 return False
             if pRoot1.val == pRoot2.val:
                 if pRoot2.left==None:
                     leftEqual=True
                 else:
                     leftEqual=getEqual(pRoot1.left,pRoot2.left)
                 if pRoot2.right==None:
                     rightEqual=True
                 else:
                     rightEqual=getEqual(pRoot1.right,pRoot2.right)
                 return leftEqual and rightEqual
             return False

         if pRoot1.val == pRoot2.val:
             ret = getEqual(pRoot1,pRoot2)
             if ret:
                 return True
         ret = self.HasSubtree(pRoot1.left,pRoot2)
         if ret:
             return True
         ret = self.HasSubtree(pRoot1.right,pRoot2)
         return ret

2019-12-09 18:40:20