if (n == nil)   return ;
    if (key < n->key)

        erase(n->l, key);

        erase(n->left, key);

    else if (key > n->key)

        erase(n->r, key);

        erase(n->right, key);

    else {
        if (n->left == nil && n->right == nil)

	      delete n, n = nil;
	  else {
	      (n->l->priority > n->r->priority) ? rotleft(n) : rotright(n);
	      erase(n, key);
	  }

            delete n, n = nil;
        else {
            (n->left->priority > n->right->priority) ? rotleft(n) : rotright(n);
            erase(n, key);
        }

    }
}
==