struct node {
  int info;
  node *left, *right;
};

typedef node *tree;

tree symmetric(tree t) {
  if (t == nullptr) return nullptr;
  tree left_sym = symmetric(t->left);
  tree right_sym = symmetric(t->right);
  tree whole_sym = new node;
  whole_sym->info = t->info;
  whole_sym->left = right_sym;
  while_sym->right = left_sym;
  return whole_sym; 
}