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.

 

 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         // IMPORTANT: Please reset any member data you declared, as

13         // the same Solution instance will be reused for each test case.

14         if(p == null && q == null)

15             return true;

16         else if(p != null && q != null && p.val == q.val) 

17             return isSameTree(p.left, q.left) && isSameTree(p.right, q.right);

18         else

19             return false;

20     }

21 }