[Leetcode]Same Tree

Given two binary trees, write a function to check if they are equal or not.

Two binary trees are considered equal if they are structurally identical and the nodes have the same value.

判断两棵树是不是一样~关于树的题目用递归来完成比较简单~时间复杂度为O(n),空间复杂度为O(logn)

# Definition for a  binary tree node# class TreeNode:#     def __init__(self, x):#         self.val = x#         self.left = None#         self.right = Noneclass Solution:    # @param p, a tree node    # @param q, a tree node    # @return a boolean    def isSameTree(self, p, q):        if p is None and q is None: return True        if p is None or q is None: return False        if p.val != q.val: return False        return self.isSameTree(p.left, q.left) and self.isSameTree(p.right, q.right)