題目
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.
題目解析
判斷兩棵樹是否相等。
實現
/**
* 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){
return false;
}
if(p.val!=q.val){
return false;
}
return isSameTree(p.left,q.left) && isSameTree(p.right,q.right);
}
}