给定两个二叉树，判断是不是相同（结构相同，值相同）的树。
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.
考虑特殊情况：
采用分支法解决：
/** * Definition for binary tree * public class TreeNode { * int val; * TreeNode left; * TreeNode right; * TreeNode(int x) { val = x; } * } */ public class Solution { public boolean isSameTree(TreeNode p, TreeNode q) { if( p==null && q==null ) return true; if( p!=null && q!=null && p.val==q.val ) return isSameTree(p.left, q.left) && isSameTree(p.right, q.right); return false; } }
原文：http://www.cnblogs.com/hf-cherish/p/4598748.html
