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.

分析：对于二叉树这一具有天然递归特性的数据结构，首先想到的就应该是递归，既然是递归，最重要就是边界了