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.
方法一:
/**
* 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) {
boolean leftsame=true;
boolean rifhtsame=true;
if(p==null&&q==null)
return true;
else if((p==null&&q!=null)||q==null&&p!=null)
return false;
else if(p.val!=q.val)
return false;
leftsame=isSameTree(p.left,q.left);
rifhtsame=isSameTree(p.right,q.right);
return leftsame&&rifhtsame;
}
}