100_same_tree.cpp

//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.

//Example 1:
//Input: p = [1,2,3], q = [1,2,3]
//Output: true

//Example 2:
//Input: p = [1,2], q = [1,null,2]
//Output: false

//Example 3:
//Input: p = [1,2,1], q = [1,1,2]
//Output: false

/**
 * Definition for a binary tree node.
 * 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 true;
    
        if (!p || !q || p->val != q->val)
            return false;
        
        return isSameTree(p->left, q->left) && isSameTree(p->right, q->right);
    }
};