[LeetCode]Same Tree解題報告

[題目描述]

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.

[解題思路]

很是常見的遞歸題，先檢查當前節點的左右節點是否相同，而後遞歸檢查左子樹和右子樹。

/**
 * Definition for binary tree
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
 * };
 */
class Solution {
public:
    bool isSameTree(TreeNode *p, TreeNode *q) {
        // Start typing your C/C++ solution below
        // DO NOT write int main() function
        if (p && q)
            if (p->val == q->val)
                    return (isSameTree(p->left, q->left) && isSameTree(p->right, q->right));
            else
                return false;
        else if ((p == NULL) && (q == NULL))
            return true;
        else
            return false;
    }
};

[源代碼]

https://github.com/rangercyh/leetcode/blob/master/Same%20Tree