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.
1 /** 2 * Definition for binary tree 3 * public class TreeNode { 4 * int val; 5 * TreeNode left; 6 * TreeNode right; 7 * TreeNode(int x) { val = x; } 8 * } 9 */ 10 public class Solution { 11 public boolean isSameTree(TreeNode p, TreeNode q) { 12 if(p==null&&q==null) 13 return true; 14 if(p==null||q==null) 15 return false; 16 if(p.val!=q.val) 17 return false; 18 return isSameTree(p.left, q.left)&&isSameTree(p.right, q.right); 19 } 20 }
原文：http://www.cnblogs.com/Phoebe815/p/4027912.html