[leet code 100] same tree

1 题目

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.

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2 思路

好久没做树的题目了，选了一道最简单的树的题目。看别人答案代码思路就很简单了，自己想，想半天思路并不是很好，各种漏洞。

参考：

https://leetcode.com/discuss/15083/five-line-java-solution-with-recursion

https://leetcode.com/discuss/3470/seeking-for-better-solution

3 代码

    public boolean isSameTree(TreeNode p,TreeNode q){
        if (p == null || q == null) return (p == q);
        return (p.val == q.val) && isSameTree(p.left, q.left) && isSameTree(p.right, q.right);
    }

时间： 2024-12-29 11:52:19

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