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