5.1.6 Same Tree

Notes:
	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.
	Solution: recursion.
	*/

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