Given two binary trees, write a function to check if they are the same or not.
Two binary trees are considered the same if they are structurally identical and the nodes have the same value.
Example 1:
Input: 1 1 / / 2 3 2 3 [1,2,3], [1,2,3] Output: true
Example 2:
Input: 1 1 / 2 2 [1,2], [1,null,2] Output: false
Example 3:
Input: 1 1 / / 2 1 1 2 [1,2,1], [1,1,2] Output: false
/** * Definition for a binary tree node. * public class TreeNode { * int val; * TreeNode left; * TreeNode right; * TreeNode(int x) { val = x; } * } */ class Solution { public boolean isSameTree(TreeNode p, TreeNode q) { if(p == null && q == null) return true; if(p == null || q == null) return false; return p.val == q.val && isSameTree(p.left, q.left) && isSameTree(p.right, q.right); } }
意思是p.val要等于q.val,并且left和right树也要为true。Damn