sameTree.cpp

// Source : https://leetcode.com/problems/same-tree/
// Author : https://github.com/xinsheng
// Date   : 2021-12-03

/*
Given the roots of two binary trees p and q, write a function to check if they are the same or not.

Two binary trees are considered the same if they are structurally identical, and the nodes have the same value.
 */

#include <string.h>
#include <iostream>
#include <string>
#include <vector>
using namespace std;

/*
Idea:
Check each element is same, then result is true.
 */

struct TreeNode {
    int val;
    TreeNode *left;
    TreeNode *right;
    TreeNode() : val(0), left(nullptr), right(nullptr) {}
    TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
    TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
};

class Solution {
public:
    bool isSameTree(TreeNode* p, TreeNode* q) {
        if(!p || !q) return (q == p);
        return (p->val == q->val) && isSameTree(p->left, q->left) && isSameTree(p->right, q->right);
    }
};