#define PROBLEM "https://yukicoder.me/problems/no/649" #include #include #include #include #include #include #include #include #include namespace suisen::internal::implicit_treap { template struct Node { using random_engine = std::mt19937; static inline random_engine rng{ 0 }; using node_type = Derived; using node_pointer = uint32_t; using priority_type = std::invoke_result_t; using size_type = uint32_t; using difference_type = int32_t; using value_type = T; using pointer = value_type*; using const_pointer = const value_type*; using reference = value_type&; using const_reference = const value_type&; static inline std::vector _nodes{}; static inline std::vector _erased{}; static constexpr node_pointer null = ~node_pointer(0); node_pointer _ch[2]{ null, null }; value_type _val; size_type _size; priority_type _priority; node_pointer _prev = null, _next = null; Node(const value_type val = {}): _val(val), _size(1), _priority(rng()) {} static void reserve(size_type capacity) { _nodes.reserve(capacity); } static bool is_null(node_pointer t) { return t == null; } static bool is_not_null(node_pointer t) { return not is_null(t); } static node_type& node(node_pointer t) { return _nodes[t]; } static const node_type& const_node(node_pointer t) { return _nodes[t]; } static value_type& value(node_pointer t) { return node(t)._val; } static value_type set_value(node_pointer t, const value_type& new_val) { return std::exchange(value(t), new_val); } static bool empty(node_pointer t) { return is_null(t); } static size_type& size(node_pointer t) { return node(t)._size; } static size_type safe_size(node_pointer t) { return empty(t) ? 0 : size(t); } static priority_type priority(node_pointer t) { return const_node(t)._priority; } static node_pointer& prev(node_pointer t) { return node(t)._prev; } static node_pointer& next(node_pointer t) { return node(t)._next; } static void link(node_pointer l, node_pointer r) { next(l) = r, prev(r) = l; } static node_pointer min(node_pointer t) { while (true) { node_type::push(t); node_pointer nt = child0(t); if (is_null(nt)) return t; t = nt; } } static node_pointer max(node_pointer t) { while (true) { node_type::push(t); node_pointer nt = child1(t); if (is_null(nt)) return t; t = nt; } } static node_pointer& child0(node_pointer t) { return node(t)._ch[0]; } static node_pointer& child1(node_pointer t) { return node(t)._ch[1]; } static node_pointer& child(node_pointer t, bool b) { return node(t)._ch[b]; } static node_pointer set_child0(node_pointer t, node_pointer cid) { return std::exchange(child0(t), cid); } static node_pointer set_child1(node_pointer t, node_pointer cid) { return std::exchange(child1(t), cid); } static node_pointer set_child(node_pointer t, bool b, node_pointer cid) { return std::exchange(child(t, b), cid); } static node_pointer update(node_pointer t) { // t : not null size(t) = safe_size(child0(t)) + safe_size(child1(t)) + 1; return t; } static void push(node_pointer) {} static node_pointer empty_node() { return null; } template static node_pointer create_node(Args &&...args) { if (_erased.size()) { node_pointer res = _erased.back(); _erased.pop_back(); node(res) = node_type(std::forward(args)...); return res; } else { node_pointer res = _nodes.size(); _nodes.emplace_back(std::forward(args)...); return res; } } static void delete_node(node_pointer t) { _erased.push_back(t); } static void delete_tree(node_pointer t) { if (is_null(t)) return; delete_tree(child0(t)); delete_tree(child1(t)); delete_node(t); } template static node_pointer build(Args &&... args) { node_pointer res = empty_node(); for (auto&& e : std::vector(std::forward(args)...)) { res = push_back(res, std::move(e)); } return res; } static std::pair split(node_pointer t, size_type k) { if (k == 0) return { null, t }; if (k == size(t)) return { t, null }; static std::vector lp{}, rp{}; while (true) { node_type::push(t); if (const size_type lsiz = safe_size(child0(t)); k <= lsiz) { if (rp.size()) set_child0(rp.back(), t); rp.push_back(t); if (k == lsiz) { if (lp.size()) set_child1(lp.back(), child0(t)); node_pointer lt = set_child0(t, null), rt = null; while (lp.size()) node_type::update(lt = lp.back()), lp.pop_back(); while (rp.size()) node_type::update(rt = rp.back()), rp.pop_back(); return { lt, rt }; } t = child0(t); } else { if (lp.size()) set_child1(lp.back(), t); lp.push_back(t); t = child1(t); k -= lsiz + 1; } } } static std::tuple split(node_pointer t, size_type l, size_type r) { auto [tlm, tr] = split(t, r); auto [tl, tm] = split(tlm, l); return { tl, tm, tr }; } // Split immediately before the first element that satisfies the condition. template static std::pair split_binary_search(node_pointer t, const Predicate& f) { if (is_null(t)) { return { null, null }; } node_type::push(t); if (f(value(t))) { auto [l, tl] = split_binary_search(child0(t), f); set_child0(t, tl); return { l, node_type::update(t) }; } else { auto [tr, r] = split_binary_search(child1(t), f); set_child1(t, tr); return { node_type::update(t), r }; } } template > static std::pair split_lower_bound(node_pointer t, const value_type& target, const Compare& comp) { return split_binary_search(t, [&](const value_type& v) { return not comp(v, target); }); } template > static std::pair split_upper_bound(node_pointer t, const value_type& target, const Compare& comp) { return split_binary_search(t, [&](const value_type& v) { return comp(target, v); }); } static node_pointer merge_impl(node_pointer tl, node_pointer tr) { if (priority(tl) < priority(tr)) { node_type::push(tr); if (node_pointer tm = child0(tr); is_null(tm)) { link(max(tl), tr); set_child0(tr, tl); } else { set_child0(tr, merge(tl, tm)); } return node_type::update(tr); } else { node_type::push(tl); if (node_pointer tm = child1(tl); is_null(tm)) { link(tl, min(tr)); set_child1(tl, tr); } else { set_child1(tl, merge(tm, tr)); } return node_type::update(tl); } } static node_pointer merge(node_pointer tl, node_pointer tr) { if (is_null(tl)) return tr; if (is_null(tr)) return tl; return merge_impl(tl, tr); } static node_pointer merge(node_pointer tl, node_pointer tm, node_pointer tr) { return merge(merge(tl, tm), tr); } static node_pointer insert_impl(node_pointer t, size_type k, node_pointer new_node) { if (is_null(t)) return new_node; static std::vector st; bool b = false; while (true) { if (is_null(t) or priority(new_node) > priority(t)) { if (is_null(t)) { t = new_node; } else { auto [tl, tr] = split(t, k); if (is_not_null(tl)) link(max(tl), new_node); if (is_not_null(tr)) link(new_node, min(tr)); set_child0(new_node, tl); set_child1(new_node, tr); t = node_type::update(new_node); } if (st.size()) { set_child(st.back(), b, t); do t = node_type::update(st.back()), st.pop_back(); while (st.size()); } return t; } else { node_type::push(t); if (const size_type lsiz = safe_size(child0(t)); k <= lsiz) { if (k == lsiz) link(new_node, t); st.push_back(t), b = false; t = child0(t); } else { if (k == lsiz + 1) link(t, new_node); st.push_back(t), b = true; t = child1(t); k -= lsiz + 1; } } } } template static node_pointer insert(node_pointer t, size_type k, Args &&...args) { return insert_impl(t, k, create_node(std::forward(args)...)); } template static node_pointer push_front(node_pointer t, Args &&...args) { return insert(t, 0, std::forward(args)...); } template static node_pointer push_back(node_pointer t, Args &&...args) { return insert(t, safe_size(t), std::forward(args)...); } // Insert a new node immediately before the first element that satisfies the condition. // Returns { node, position to insert } template static std::pair insert_binary_search_impl(node_pointer t, const Predicate& f, node_pointer new_node) { if (is_null(t)) { return { new_node, 0 }; } if (priority(new_node) > priority(t)) { auto [tl, tr] = split_binary_search(t, f); if (is_not_null(tl)) link(max(tl), t); if (is_not_null(tr)) link(min(tr), t); set_child0(new_node, tl); set_child1(new_node, tr); return { node_type::update(new_node), safe_size(tl) }; } else { node_type::push(t); if (f(value(t))) { auto [c0, pos] = insert_binary_search_impl(child0(t), f, new_node); set_child0(t, c0); if (is_null(next(new_node))) link(new_node, t); return { node_type::update(t), pos }; } else { auto [c1, pos] = insert_binary_search_impl(child1(t), f, new_node); set_child1(t, c1); if (is_null(prev(new_node))) link(t, new_node); return { node_type::update(t), pos + safe_size(child0(t)) + 1 }; } } } template static std::pair insert_binary_search(node_pointer t, const Predicate& f, Args &&...args) { return insert_binary_search_impl(t, f, create_node(std::forward(args)...)); } template > static std::pair insert_lower_bound(node_pointer t, const value_type& v, Compare comp) { return insert_binary_search(t, [&](const value_type& x) { return not comp(x, v); }, v); } template > static std::pair insert_upper_bound(node_pointer t, const value_type& v, Compare comp) { return insert_binary_search(t, [&](const value_type& x) { return comp(v, x); }, v); } static std::pair erase(node_pointer t, size_type k) { node_type::push(t); if (const size_type lsiz = safe_size(child0(t)); k == lsiz) { delete_node(t); return { merge(child0(t), child1(t)), std::move(value(t)) }; } else if (k < lsiz) { auto [c0, v] = erase(child0(t), k); set_child0(t, c0); if (is_not_null(c0) and k == lsiz - 1) link(max(c0), t); return { node_type::update(t), std::move(v) }; } else { auto [c1, v] = erase(child1(t), k - (lsiz + 1)); set_child1(t, c1); if (is_not_null(c1) and k == lsiz + 1) link(t, min(c1)); return { node_type::update(t), std::move(v) }; } } static std::pair pop_front(node_pointer t) { return erase(t, 0); } static std::pair pop_back(node_pointer t) { return erase(t, safe_size(t) - 1); } // Erase the first element that satisfies the condition f if it also satisfies the condition g. // returns { node, optional(position, value) } template static std::pair>> erase_binary_search(node_pointer t, const Predicate& f, const RemovePredicate& g) { if (is_null(t)) return { null, std::nullopt }; node_type::push(t); if (f(value(t))) { auto [c0, erased] = erase_binary_search(child0(t), f, g); if (erased) { set_child0(t, c0); size_type& pos = erased->first; if (is_not_null(c0) and pos == safe_size(c0)) link(max(c0), t); return { node_type::update(t), std::move(erased) }; } else if (g(value(t))) { delete_node(t); std::pair erased_entry{ safe_size(child0(t)), std::move(value(t)) }; return { merge(child0(t), child1(t)), std::move(erased_entry) }; } else { return { t, std::nullopt }; } } else { auto [c1, erased] = erase_binary_search(child1(t), f, g); if (erased) { set_child1(t, c1); size_type& pos = erased->first; if (is_not_null(c1) and pos == 0) link(t, min(c1)); pos += safe_size(child0(t)) + 1; return { node_type::update(t), std::move(erased) }; } else { return { t, std::nullopt }; } } } template > static std::pair>> erase_lower_bound(node_pointer t, const value_type& v, Compare comp) { return erase_binary_search( t, [&](const value_type& x) { return not comp(x, v); }, [] { return true; } ); } template > static std::pair>> erase_upper_bound(node_pointer t, const value_type& v, Compare comp) { return erase_binary_search( t, [&](const value_type& x) { return comp(v, x); }, [] { return true; } ); } template > static std::pair>> erase_if_exists(node_pointer t, const value_type& v, Compare comp) { return erase_binary_search( t, [&](const value_type& x) { return not comp(x, v); }, [&](const value_type& x) { return not comp(v, x); } ); } static node_pointer rotate(node_pointer t, size_type k) { auto [tl, tr] = split(t, k); return merge(tr, tl); } static node_pointer rotate(node_pointer t, size_type l, size_type m, size_type r) { auto [tl, tm, tr] = split(t, l, r); return merge(tl, rotate(tm, m - l), tr); } static value_type& get(node_pointer t, size_type k) { while (true) { node_type::push(t); if (const size_type lsiz = safe_size(child0(t)); k == lsiz) { return value(t); } else if (k < lsiz) { t = child0(t); } else { k -= lsiz + 1; t = child1(t); } } } template static node_pointer set_update(node_pointer t, size_type k, const Func& f) { node_type::push(t); if (const size_type lsiz = safe_size(child0(t)); k == lsiz) { value_type& val = value(t); val = f(const_cast(val)); } else if (k < lsiz) { set_child0(t, set_update(child0(t), k, f)); } else { set_child1(t, set_update(child1(t), k - (lsiz + 1), f)); } return node_type::update(t); } static std::vector dump(node_pointer t) { std::vector res; res.reserve(safe_size(t)); auto rec = [&](auto rec, node_pointer t) -> void { if (is_null(t)) return; node_type::push(t); rec(rec, child0(t)); res.push_back(value(t)); rec(rec, child1(t)); }; rec(rec, t); return res; } // Find the first element that satisfies the condition f : (value, index) -> { false, true }. // Returns { optional(value), position } template static std::pair> binary_search(node_pointer t, const Predicate& f) { node_pointer res = null; int ng = -1, ok = safe_size(t); while (ok - ng > 1) { node_type::push(t); if (const int root = ng + safe_size(child0(t)) + 1; f(value(t), root)) { res = t; ok = root, t = child0(t); } else { ng = root, t = child1(t); } } if (is_null(res)) { return { ok, std::nullopt }; } else { return { ok, value(res) }; } } // comp(T t, U u) = (t < u) template > static std::pair> lower_bound(node_pointer t, const U& target, Compare comp) { return binary_search(t, [&](const value_type& v, int) { return not comp(v, target); }); } // comp(T u, U t) = (u < t) template > static std::pair> upper_bound(node_pointer t, const U& target, Compare comp) { return binary_search(t, [&](const value_type& v, int) { return comp(target, v); }); } template struct NodeIterator { static constexpr bool constant = constant_; static constexpr bool reversed = reversed_; using difference_type = Node::difference_type; using value_type = Node::value_type; using pointer = std::conditional_t; using reference = std::conditional_t; using iterator_cateogory = std::random_access_iterator_tag; NodeIterator(): root(null), index(0) {} reference operator*() { if (is_null(cur) and index != safe_size(root)) { cur = root; for (size_type k = index;;) { node_type::push(cur); if (size_type siz = safe_size(child(cur, reversed)); k == siz) { break; } else if (k < siz) { cur = child(cur, reversed); } else { cur = child(cur, not reversed); k -= siz + 1; } } } return value(cur); } reference operator[](difference_type k) const { return *((*this) + k); } NodeIterator& operator++() { return *this += 1; } NodeIterator& operator--() { return *this -= 1; } NodeIterator& operator+=(difference_type k) { return suc(+k), * this; } NodeIterator& operator-=(difference_type k) { return suc(-k), * this; } NodeIterator operator++(int) { NodeIterator res = *this; ++(*this); return res; } NodeIterator operator--(int) { NodeIterator res = *this; --(*this); return res; } friend NodeIterator operator+(NodeIterator it, difference_type k) { return it += k; } friend NodeIterator operator+(difference_type k, NodeIterator it) { return it += k; } friend NodeIterator operator-(NodeIterator it, difference_type k) { return it -= k; } friend difference_type operator-(const NodeIterator& lhs, const NodeIterator& rhs) { return lhs.index - rhs.index; } friend bool operator==(const NodeIterator& lhs, const NodeIterator& rhs) { return lhs.index == rhs.index; } friend bool operator!=(const NodeIterator& lhs, const NodeIterator& rhs) { return lhs.index != rhs.index; } friend bool operator<(const NodeIterator& lhs, const NodeIterator& rhs) { return lhs.index < rhs.index; } friend bool operator>(const NodeIterator& lhs, const NodeIterator& rhs) { return lhs.index > rhs.index; } friend bool operator<=(const NodeIterator& lhs, const NodeIterator& rhs) { return lhs.index <= rhs.index; } friend bool operator>=(const NodeIterator& lhs, const NodeIterator& rhs) { return lhs.index >= rhs.index; } static NodeIterator begin(node_pointer root) { return NodeIterator(root, 0); } static NodeIterator end(node_pointer root) { return NodeIterator(root, safe_size(root)); } private: node_pointer root; size_type index; node_pointer cur = null; // it==end() or uninitialized (updates only index) NodeIterator(node_pointer root, size_type index): root(root), index(index) {} void suc(difference_type k) { index += k; if (index == safe_size(root) or std::abs(k) >= 10) cur = null; if (is_null(cur)) return; const bool positive = k < 0 ? (k = -k, reversed) : not reversed; if (positive) { while (k-- > 0) cur = next(cur); } else { while (k-- > 0) cur = prev(cur); } } }; using iterator = NodeIterator; using reverse_iterator = NodeIterator; using const_iterator = NodeIterator; using const_reverse_iterator = NodeIterator; static iterator begin(node_pointer t) { return iterator::begin(t); } static iterator end(node_pointer t) { return iterator::end(t); } static reverse_iterator rbegin(node_pointer t) { return reverse_iterator::begin(t); } static reverse_iterator rend(node_pointer t) { return reverse_iterator::end(t); } static const_iterator cbegin(node_pointer t) { return const_iterator::begin(t); } static const_iterator cend(node_pointer t) { return const_iterator::end(t); } static const_reverse_iterator crbegin(node_pointer t) { return const_reverse_iterator::begin(t); } static const_reverse_iterator crend(node_pointer t) { return const_reverse_iterator::end(t); } }; } // namespace suisen::internal::implicit_treap namespace suisen { namespace internal::implicit_treap { template struct DefaultNode: Node> { using base = Node>; using base::base; }; } template class DynamicArray { using node_type = internal::implicit_treap::DefaultNode; using node_pointer = typename node_type::node_pointer; node_pointer _root; struct node_pointer_construct {}; DynamicArray(node_pointer root, node_pointer_construct): _root(root) {} public: using value_type = typename node_type::value_type; DynamicArray(): _root(node_type::empty_node()) {} explicit DynamicArray(size_t n, const value_type& fill_value = {}): _root(node_type::build(n, fill_value)) {} template DynamicArray(const std::vector& dat) : _root(node_type::build(dat.begin(), dat.end())) {} void free() { node_type::delete_tree(_root); _root = node_type::empty_node(); } void clear() { free(); } static void reserve(size_t capacity) { node_type::reserve(capacity); } bool empty() const { return node_type::empty(_root); } int size() const { return node_type::safe_size(_root); } value_type& operator[](size_t k) { assert(k < size_t(size())); return node_type::get(_root, k); } const value_type& operator[](size_t k) const { assert(k < size_t(size())); return node_type::get(_root, k); } value_type& front() { return (*this)[0]; } value_type& back() { return (*this)[size() - 1]; } const value_type& front() const { return (*this)[0]; } const value_type& back() const { return (*this)[size() - 1]; } void insert(size_t k, const value_type& val) { assert(k <= size_t(size())); _root = node_type::insert(_root, k, val); } void push_front(const value_type& val) { _root = node_type::push_front(_root, val); } void push_back(const value_type& val) { _root = node_type::push_back(_root, val); } // Insert a new value immediately before the first element that satisfies the condition f. // Returns: the inserted position // Requirements: f(A[i]) must be monotonic template int insert_binary_search(const value_type& val, const Predicate &f) { int pos; std::tie(_root, pos) = node_type::insert_binary_search(_root, f, val); return pos; } // Insert a new value immediately before the first element that is greater than or equal to the new value. // Returns: the inserted position // Requirements: sequence is sorted template > int insert_lower_bound(const value_type& val, const Compare &comp = {}) { int pos; std::tie(_root, pos) = node_type::insert_lower_bound(_root, val, comp); return pos; } // Insert a new value immediately before the first element that is greater than the new value. // Returns: the inserted position // Requirements: sequence is sorted template > int insert_upper_bound(const value_type& val, const Compare &comp = {}) { int pos; std::tie(_root, pos) = node_type::insert_upper_bound(_root, val, comp); return pos; } value_type erase(size_t k) { assert(k <= size_t(size())); value_type v; std::tie(_root, v) = node_type::erase(_root, k); return v; } value_type pop_front() { return erase(0); } value_type pop_back() { return erase(size() - 1); } // Erase the first element that satisfies the condition f if it also satisfies the condition g. // returns optional(position, value) // Requirements: sequence is sorted template std::optional> erase_binary_search(const Predicate &f, const RemovePredicate& g) { auto [root, erased] = node_type::erase_binary_search(_root, f, g); _root = root; if (erased) { return std::pair{ erased->first, erased->second }; } else { return std::nullopt; } } // Erase the first element that is greater than or equal to val. // returns optional(position, value) // Requirements: sequence is sorted template > std::optional> erase_lower_bound(const value_type &val, const Compare &comp = {}) { auto [root, erased] = node_type::erase_lower_bound(_root, val, comp); _root = root; if (erased) { return std::pair{ erased->first, erased->second }; } else { return std::nullopt; } } // Erase the first element that is greater than val. // returns optional(position, value) // Requirements: sequence is sorted template > std::optional> erase_upper_bound(const value_type &val, const Compare &comp = {}) { auto [root, erased] = node_type::erase_upper_bound(_root, val, comp); _root = root; if (erased) { return std::pair{ erased->first, erased->second }; } else { return std::nullopt; } } // Erase the first element that is equal to val. // returns optional(position, value) // Requirements: sequence is sorted template > std::optional> erase_if_exists(const value_type &val, const Compare &comp = {}) { auto [root, erased] = node_type::erase_if_exists(_root, val, comp); _root = root; if (erased) { return std::pair{ erased->first, erased->second }; } else { return std::nullopt; } } // Split immediately before the k-th element. DynamicArray split(size_t k) { assert(k <= size_t(size())); node_pointer root_r; std::tie(_root, root_r) = node_type::split(_root, k); return DynamicArray(root_r, node_pointer_construct{}); } // Split immediately before the first element that satisfies the condition. // Requirements: f(A[i]) must be monotonic template DynamicArray split_binary_search(const Predicate &f) { node_pointer root_r; std::tie(_root, root_r) = node_type::split_binary_search(_root, f); return DynamicArray(root_r, node_pointer_construct{}); } // Split immediately before the first element that is greater than or equal to val. // Requirements: sequence is sorted template > DynamicArray split_lower_bound(const value_type &val, const Compare &comp = {}) { node_pointer root_r; std::tie(_root, root_r) = node_type::split_lower_bound(_root, val, comp); return DynamicArray(root_r, node_pointer_construct{}); } // Split immediately before the first element that is greater than val. // Requirements: sequence is sorted template > DynamicArray split_upper_bound(const value_type &val, const Compare &comp = {}) { node_pointer root_r; std::tie(_root, root_r) = node_type::split_upper_bound(_root, val, comp); return DynamicArray(root_r, node_pointer_construct{}); } void merge(DynamicArray r) { _root = node_type::merge(_root, r._root); } void rotate(size_t k) { assert(k <= size_t(size())); _root = node_type::rotate(_root, k); } void rotate(size_t l, size_t m, size_t r) { assert(l <= m and m <= r and r <= size_t(size())); _root = node_type::rotate(_root, l, m, r); } std::vector dump() const { return node_type::dump(_root); } // Find the first element that satisfies the condition f. // Returns { position, optional(value) } // Requirements: f(A[i]) must be monotonic template std::pair> binary_search(const Predicate& f) const { auto [pos, val] = node_type::binary_search(_root, f); return { pos, std::move(val) }; } // comp(T t, U u) = (t < u) // Requirements: sequence is sorted template > std::pair> lower_bound(const U& target, Compare comp = {}) const { auto [pos, val] = node_type::lower_bound(_root, target, comp); return { pos, std::move(val) }; } // comp(T u, U t) = (u < t) // Requirements: sequence is sorted template > std::pair> upper_bound(const U& target, Compare comp = {}) const { auto [pos, val] = node_type::upper_bound(_root, target, comp); return { pos, std::move(val) }; } using iterator = typename node_type::iterator; using reverse_iterator = typename node_type::reverse_iterator; using const_iterator = typename node_type::const_iterator; using const_reverse_iterator = typename node_type::const_reverse_iterator; iterator begin() { return node_type::begin(_root); } iterator end() { return node_type::end(_root); } reverse_iterator rbegin() { return node_type::rbegin(_root); } reverse_iterator rend() { return node_type::rend(_root); } const_iterator begin() const { return cbegin(); } const_iterator end() const { return cend(); } const_reverse_iterator rbegin() const { return crbegin(); } const_reverse_iterator rend() const { return crend(); } const_iterator cbegin() const { return node_type::cbegin(_root); } const_iterator cend() const { return node_type::cend(_root); } const_reverse_iterator crbegin() const { return node_type::crbegin(_root); } const_reverse_iterator crend() const { return node_type::crend(_root); } }; } // namespace suisen int main() { std::ios::sync_with_stdio(false); std::cin.tie(nullptr); int q, k; std::cin >> q >> k; using suisen::DynamicArray; DynamicArray a; while (q-- > 0) { int t; std::cin >> t; if (t == 1) { long long v; std::cin >> v; a.insert_lower_bound(v); } else { if (a.size() < k) { std::cout << -1 << '\n'; } else { std::cout << a.erase(k - 1) << '\n'; } } } }