結果
問題 | No.1553 Lovely City |
ユーザー |
![]() |
提出日時 | 2021-06-19 00:05:55 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 243 ms / 2,000 ms |
コード長 | 44,354 bytes |
コンパイル時間 | 3,002 ms |
コンパイル使用メモリ | 286,628 KB |
最終ジャッジ日時 | 2025-01-22 09:52:45 |
ジャッジサーバーID (参考情報) |
judge5 / judge4 |
(要ログイン)
ファイルパターン | 結果 |
---|---|
sample | AC * 2 |
other | AC * 26 |
ソースコード
#line 1 "other-workspace\\y.cc"// #undef _GLIBCXX_DEBUG// #define NDEBUG#include <bits/extc++.h>#line 2 "Library\\lib\\alias"/*** @file alias* @brief Alias*/#line 10 "Library\\lib\\alias"#line 2 "Library\\lib\\bit"#if __cplusplus > 201703L#include <bit>#elif __cplusplus > 201402L#ifndef _GLIBCXX_BIT#define _GLIBCXX_BIT 1#include <limits>#include <type_traits>namespace std {template <typename _Tp> constexpr int __countl_zero(_Tp __x) noexcept {constexpr auto _Nd = numeric_limits<_Tp>::digits;if (__x == 0) return _Nd;constexpr auto _Nd_ull = numeric_limits<unsigned long long>::digits;constexpr auto _Nd_ul = numeric_limits<unsigned long>::digits;constexpr auto _Nd_u = numeric_limits<unsigned>::digits;if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_u) {constexpr int __diff = _Nd_u - _Nd;return __builtin_clz(__x) - __diff;} else if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_ul) {constexpr int __diff = _Nd_ul - _Nd;return __builtin_clzl(__x) - __diff;} else if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_ull) {constexpr int __diff = _Nd_ull - _Nd;return __builtin_clzll(__x) - __diff;} else // (_Nd > _Nd_ull){static_assert(_Nd <= (2 * _Nd_ull),"Maximum supported integer size is 128-bit");unsigned long long __high = __x >> _Nd_ull;if (__high != 0) {constexpr int __diff = (2 * _Nd_ull) - _Nd;return __builtin_clzll(__high) - __diff;}constexpr auto __max_ull = numeric_limits<unsigned long long>::max();unsigned long long __low = __x & __max_ull;return (_Nd - _Nd_ull) + __builtin_clzll(__low);}}template <typename _Tp> constexpr int __countr_zero(_Tp __x) noexcept {constexpr auto _Nd = numeric_limits<_Tp>::digits;if (__x == 0) return _Nd;constexpr auto _Nd_ull = numeric_limits<unsigned long long>::digits;constexpr auto _Nd_ul = numeric_limits<unsigned long>::digits;constexpr auto _Nd_u = numeric_limits<unsigned>::digits;if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_u)return __builtin_ctz(__x);else if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_ul)return __builtin_ctzl(__x);else if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_ull)return __builtin_ctzll(__x);else // (_Nd > _Nd_ull){static_assert(_Nd <= (2 * _Nd_ull),"Maximum supported integer size is 128-bit");constexpr auto __max_ull = numeric_limits<unsigned long long>::max();unsigned long long __low = __x & __max_ull;if (__low != 0) return __builtin_ctzll(__low);unsigned long long __high = __x >> _Nd_ull;return __builtin_ctzll(__high) + _Nd_ull;}}template <typename _Tp> constexpr int __popcount(_Tp __x) noexcept {constexpr auto _Nd = numeric_limits<_Tp>::digits;if (__x == 0) return 0;constexpr auto _Nd_ull = numeric_limits<unsigned long long>::digits;constexpr auto _Nd_ul = numeric_limits<unsigned long>::digits;constexpr auto _Nd_u = numeric_limits<unsigned>::digits;if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_u)return __builtin_popcount(__x);else if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_ul)return __builtin_popcountl(__x);else if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_ull)return __builtin_popcountll(__x);else // (_Nd > _Nd_ull){static_assert(_Nd <= (2 * _Nd_ull),"Maximum supported integer size is 128-bit");constexpr auto __max_ull = numeric_limits<unsigned long long>::max();unsigned long long __low = __x & __max_ull;unsigned long long __high = __x >> _Nd_ull;return __builtin_popcountll(__low) + __builtin_popcountll(__high);}}template <typename _Tp> constexpr _Tp __bit_ceil(_Tp __x) noexcept {constexpr auto _Nd = numeric_limits<_Tp>::digits;if (__x == 0 || __x == 1) return 1;auto __shift_exponent = _Nd - __countl_zero((_Tp)(__x - 1u));#ifdef _GLIBCXX_HAVE_BUILTIN_IS_CONSTANT_EVALUATEDif (!__builtin_is_constant_evaluated()) {__glibcxx_assert(__shift_exponent != numeric_limits<_Tp>::digits);}#endifusing __promoted_type = decltype(__x << 1);if _GLIBCXX17_CONSTEXPR (!is_same<__promoted_type, _Tp>::value) {const int __extra_exp = sizeof(__promoted_type) / sizeof(_Tp) / 2;__shift_exponent |= (__shift_exponent & _Nd) << __extra_exp;}return (_Tp)1u << __shift_exponent;}template <typename _Tp> constexpr _Tp __bit_floor(_Tp __x) noexcept {constexpr auto _Nd = numeric_limits<_Tp>::digits;if (__x == 0) return 0;return (_Tp)1u << (_Nd - __countl_zero((_Tp)(__x >> 1)));}template <typename _Tp> constexpr _Tp __bit_width(_Tp __x) noexcept {constexpr auto _Nd = numeric_limits<_Tp>::digits;return _Nd - __countl_zero(__x);}} // namespace std#endif#endif#line 2 "Library\\lib\\limits"#line 4 "Library\\lib\\limits"namespace workspace {template <class _Tp> struct numeric_limits : std::numeric_limits<_Tp> {};#ifdef __SIZEOF_INT128__template <> struct numeric_limits<__uint128_t> {constexpr static __uint128_t max() { return ~__uint128_t(0); }constexpr static __uint128_t min() { return 0; }};template <> struct numeric_limits<__int128_t> {constexpr static __int128_t max() {return numeric_limits<__uint128_t>::max() >> 1;}constexpr static __int128_t min() { return -max() - 1; }};#endif} // namespace workspace#line 13 "Library\\lib\\alias"namespace workspace {constexpr static char eol = '\n';using namespace std;using i32 = int_least32_t;using u32 = uint_least32_t;using i64 = int_least64_t;using u64 = uint_least64_t;#ifdef __SIZEOF_INT128__using i128 = __int128_t;using u128 = __uint128_t;#else#warning 128-bit integer is not available.#endiftemplate <class _T1, class _T2,typename = decltype(std::declval<const _T2 &>() <std::declval<const _T1 &>())>constexprtypename std::conditional<std::is_same<_T1, _T2>::value, const _T1 &,typename std::common_type<_T1, _T2>::type>::typemin(const _T1 &__x, const _T2 &__y) noexcept {return __y < __x ? __y : __x;}template <class _T1, class _T2, class _Compare,typename = decltype(std::declval<_Compare>()(std::declval<const _T2 &>(), std::declval<const _T1 &>()))>constexprtypename std::conditional<std::is_same<_T1, _T2>::value, const _T1 &,typename std::common_type<_T1, _T2>::type>::typemin(const _T1 &__x, const _T2 &__y, _Compare __comp) noexcept {return __comp(__y, __x) ? __y : __x;}template <class _Tp, typename = decltype(std::declval<const _Tp &>() <std::declval<const _Tp &>())>constexpr _Tp min(std::initializer_list<_Tp> __x) noexcept {return *std::min_element(__x.begin(), __x.end());}template <class _Tp, class _Compare,typename = decltype(std::declval<_Compare>()(std::declval<const _Tp &>(), std::declval<const _Tp &>()))>constexpr _Tp min(std::initializer_list<_Tp> __x, _Compare __comp) noexcept {return *std::min_element(__x.begin(), __x.end(), __comp);}template <class _T1, class _T2,typename = decltype(std::declval<const _T1 &>() <std::declval<const _T2 &>())>constexprtypename std::conditional<std::is_same<_T1, _T2>::value, const _T1 &,typename std::common_type<_T1, _T2>::type>::typemax(const _T1 &__x, const _T2 &__y) noexcept {return __x < __y ? __y : __x;}template <class _T1, class _T2, class _Compare,typename = decltype(std::declval<_Compare>()(std::declval<const _T1 &>(), std::declval<const _T2 &>()))>constexprtypename std::conditional<std::is_same<_T1, _T2>::value, const _T1 &,typename std::common_type<_T1, _T2>::type>::typemax(const _T1 &__x, const _T2 &__y, _Compare __comp) noexcept {return __comp(__x, __y) ? __y : __x;}template <class _Tp, typename = decltype(std::declval<const _Tp &>() <std::declval<const _Tp &>())>constexpr _Tp max(std::initializer_list<_Tp> __x) noexcept {return *std::max_element(__x.begin(), __x.end());}template <class _Tp, class _Compare,typename = decltype(std::declval<_Compare>()(std::declval<const _Tp &>(), std::declval<const _Tp &>()))>constexpr _Tp max(std::initializer_list<_Tp> __x, _Compare __comp) noexcept {return *std::max_element(__x.begin(), __x.end(), __comp);}#ifdef _GLIBCXX_BITtemplate <typename _Tp> constexpr _Tp __bsf(_Tp __x) noexcept {return std::__countr_zero(__x);}template <typename _Tp> constexpr _Tp __bsr(_Tp __x) noexcept {return std::__bit_width(__x) - 1;}#endif} // namespace workspace#line 6 "other-workspace\\y.cc"// #include "lib/cxx20"#line 1 "Library\\lib\\direct"#ifdef ONLINE_JUDGE#pragma GCC optimize("O3")#pragma GCC target("avx,avx2")#pragma GCC optimize("unroll-loops")#endif#line 8 "other-workspace\\y.cc"// #include "lib/opt"#line 2 "Library\\src\\sys\\call_once.hpp"/*** @file call_once.hpp* @brief Call Once*/#line 9 "Library\\src\\sys\\call_once.hpp"namespace workspace {/*** @brief Call once.*/template <class _F> void call_once(_F &&__f) {static std::unordered_set<void *> __called;if (__called.count(std::addressof(__f))) return;__called.emplace(std::addressof(__f));__f();}} // namespace workspace#line 2 "Library\\src\\sys\\clock.hpp"/*** @file clock.hpp* @brief Clock*/#line 9 "Library\\src\\sys\\clock.hpp"namespace workspace {using namespace std::chrono;namespace internal {// The start time of the program.const auto start_time{system_clock::now()};} // namespace internal/*** @return Elapsed time of the program.*/decltype(auto) elapsed() noexcept {const auto end_time{system_clock::now()};return duration_cast<milliseconds>(end_time - internal::start_time).count();}} // namespace workspace#line 2 "Library\\src\\sys\\ejection.hpp"/*** @file ejection.hpp* @brief Ejection*/#line 9 "Library\\src\\sys\\ejection.hpp"namespace workspace {namespace internal {struct ejection {bool exit = 0;};} // namespace internal/*** @brief eject from a try block, throw nullptr* @param arg output*/template <class Tp> void eject(Tp const &arg) {std::cout << arg << "\n";throw internal::ejection{};}void exit() { throw internal::ejection{true}; }} // namespace workspace#line 2 "Library\\src\\sys\\iteration.hpp"/*** @file iteration.hpp* @brief Case Iteration*/#line 9 "Library\\src\\sys\\iteration.hpp"#line 11 "Library\\src\\sys\\iteration.hpp"namespace workspace {void main();struct {// 1-indexedunsigned current{0};unsigned total{1};void read() { (std::cin >> total).ignore(); }int iterate() {static bool once = false;assert(!once);once = true;while (current++ < total) {try {main();} catch (internal::ejection const& status) {if (status.exit) break;}}return 0;}} case_info;} // namespace workspace#line 2 "Library\\lib\\utils"// #include "src/utils/cached.hpp"#line 2 "Library\\src\\utils\\cat.hpp"/*** @file cat.hpp* @brief Cat*/#line 9 "Library\\src\\utils\\cat.hpp"#line 2 "Library\\lib\\cxx17"#ifndef _CXX17_CONSTEXPR#if __cplusplus >= 201703L#define _CXX17_CONSTEXPR constexpr#else#define _CXX17_CONSTEXPR#endif#endif#if __cplusplus < 201703Lnamespace std {/*** @brief Return the size of a container.* @param __cont Container.*/template <typename _Container>constexpr auto size(const _Container& __cont) noexcept(noexcept(__cont.size()))-> decltype(__cont.size()) {return __cont.size();}/*** @brief Return the size of an array.*/template <typename _Tp, size_t _Nm>constexpr size_t size(const _Tp (&)[_Nm]) noexcept {return _Nm;}} // namespace std#endif#line 11 "Library\\src\\utils\\cat.hpp"namespace workspace {/*** @brief Concatenate two sequences.** @param __c1* @param __c2* @return Concatenated sequence.*/template <class _C1, class _C2>constexpr decltype(auto) cat(_C1 &&__c1, _C2 &&__c2) noexcept {auto __c = std::forward<_C1>(__c1);if _CXX17_CONSTEXPR (std::is_rvalue_reference<decltype(__c2)>::value)__c.insert(std::end(__c), std::make_move_iterator(std::begin(__c2)),std::make_move_iterator(std::end(__c2)));else__c.insert(std::end(__c), std::cbegin(__c2), std::cend(__c2));return __c;}/*** @return Concatenated sequence.*/template <class _C1, class _C2, class... _Args>constexpr decltype(auto) cat(_C1 &&__c1, _C2 &&__c2,_Args &&...__args) noexcept {return cat(cat(std::forward<_C1>(__c1), std::forward<_C2>(__c2)),std::forward<_Args>(__args)...);}} // namespace workspace#line 2 "Library\\src\\utils\\chval.hpp"/*** @file chval.hpp* @brief Change Less/Greater*/#line 9 "Library\\src\\utils\\chval.hpp"namespace workspace {/*** @brief Substitute __y for __x if __y < __x.* @param __x Reference* @param __y Comparison target* @return Whether or not __x is updated.*/template <class _T1, class _T2,typename = decltype(std::declval<_T2>() < std::declval<_T1 &>())>typename std::enable_if<std::is_assignable<_T1 &, _T2>::value, bool>::type chle(_T1 &__x, _T2 &&__y) noexcept {return __y < __x ? __x = std::forward<_T2>(__y), true : false;}/*** @brief Substitute __y for __x if __x < __y.* @param __x Reference* @param __y Comparison target* @return Whether or not __x is updated.*/template <class _T1, class _T2,typename = decltype(std::declval<_T1 &>() < std::declval<_T2>())>typename std::enable_if<std::is_assignable<_T1 &, _T2>::value, bool>::type chgr(_T1 &__x, _T2 &&__y) noexcept {return __x < __y ? __x = std::forward<_T2>(__y), true : false;}/*** @brief Substitute __y for __x if __comp(__y, __x) is true.* @param __x Reference* @param __y Comparison target* @param __comp Compare function object* @return Whether or not __x is updated.*/template <class _T1, class _T2, class _Compare,typename = decltype(std::declval<_Compare>()(std::declval<_T2>(),std::declval<_T1 &>()))>typename std::enable_if<std::is_assignable<_T1 &, _T2>::value, bool>::type chle(_T1 &__x, _T2 &&__y, _Compare __comp) noexcept {return __comp(__y, __x) ? __x = std::forward<_T2>(__y), true : false;}/*** @brief Substitute __y for __x if __comp(__x, __y) is true.* @param __x Reference* @param __y Comparison target* @param __comp Compare function object* @return Whether or not __x is updated.*/template <class _T1, class _T2, class _Compare,typename = decltype(std::declval<_Compare>()(std::declval<_T1 &>(),std::declval<_T2>()))>typename std::enable_if<std::is_assignable<_T1 &, _T2>::value, bool>::type chgr(_T1 &__x, _T2 &&__y, _Compare __comp) noexcept {return __comp(__x, __y) ? __x = std::forward<_T2>(__y), true : false;}} // namespace workspace#line 1 "Library\\src\\utils\\compare.hpp"/*** @file compare.hpp* @brief Compare*/#line 2 "Library\\src\\utils\\sfinae.hpp"/*** @file sfinae.hpp* @brief SFINAE*/#line 10 "Library\\src\\utils\\sfinae.hpp"#include <type_traits>#ifndef __INT128_DEFINED__#ifdef __SIZEOF_INT128__#define __INT128_DEFINED__ 1#else#define __INT128_DEFINED__ 0#endif#endifnamespace std {#if __INT128_DEFINED__template <> struct make_signed<__uint128_t> { using type = __int128_t; };template <> struct make_signed<__int128_t> { using type = __int128_t; };template <> struct make_unsigned<__uint128_t> { using type = __uint128_t; };template <> struct make_unsigned<__int128_t> { using type = __uint128_t; };template <> struct is_signed<__uint128_t> : std::false_type {};template <> struct is_signed<__int128_t> : std::true_type {};template <> struct is_unsigned<__uint128_t> : std::true_type {};template <> struct is_unsigned<__int128_t> : std::false_type {};#endif} // namespace stdnamespace workspace {template <class Tp, class... Args> struct variadic_front { using type = Tp; };template <class... Args> struct variadic_back;template <class Tp> struct variadic_back<Tp> { using type = Tp; };template <class Tp, class... Args> struct variadic_back<Tp, Args...> {using type = typename variadic_back<Args...>::type;};template <class type, template <class> class trait>using enable_if_trait_type = typename std::enable_if<trait<type>::value>::type;/*** @brief Return type of subscripting ( @c [] ) access.*/template <class _Tp>using subscripted_type =typename std::decay<decltype(std::declval<_Tp&>()[0])>::type;template <class Container>using element_type = typename std::decay<decltype(*std::begin(std::declval<Container&>()))>::type;template <class _Tp, class = std::nullptr_t>struct has_begin : std::false_type {};template <class _Tp>struct has_begin<_Tp, decltype(std::begin(std::declval<_Tp>()), nullptr)>: std::true_type {};template <class _Tp, class = void> struct has_mod : std::false_type {};template <class _Tp>struct has_mod<_Tp, std::__void_t<decltype(_Tp::mod)>> : std::true_type {};template <class _Tp, class = void> struct is_integral_ext : std::false_type {};template <class _Tp>struct is_integral_ext<_Tp, typename std::enable_if<std::is_integral<_Tp>::value>::type>: std::true_type {};#if __INT128_DEFINED__template <> struct is_integral_ext<__int128_t> : std::true_type {};template <> struct is_integral_ext<__uint128_t> : std::true_type {};#endif#if __cplusplus >= 201402template <class _Tp>constexpr static bool is_integral_ext_v = is_integral_ext<_Tp>::value;#endiftemplate <typename _Tp, typename = void> struct multiplicable_uint {using type = uint_least32_t;};template <typename _Tp>struct multiplicable_uint<_Tp,typename std::enable_if<(2 < sizeof(_Tp)) &&(!__INT128_DEFINED__ || sizeof(_Tp) <= 4)>::type> {using type = uint_least64_t;};#if __INT128_DEFINED__template <typename _Tp>struct multiplicable_uint<_Tp,typename std::enable_if<(4 < sizeof(_Tp))>::type> {using type = __uint128_t;};#endiftemplate <typename _Tp> struct multiplicable_int {using type =typename std::make_signed<typename multiplicable_uint<_Tp>::type>::type;};template <typename _Tp> struct multiplicable {using type = std::conditional_t<is_integral_ext<_Tp>::value,std::conditional_t<std::is_signed<_Tp>::value,typename multiplicable_int<_Tp>::type,typename multiplicable_uint<_Tp>::type>,_Tp>;};template <class> struct first_arg { using type = void; };template <class _R, class _Tp, class... _Args>struct first_arg<_R(_Tp, _Args...)> {using type = _Tp;};template <class _R, class _Tp, class... _Args>struct first_arg<_R (*)(_Tp, _Args...)> {using type = _Tp;};template <class _G, class _R, class _Tp, class... _Args>struct first_arg<_R (_G::*)(_Tp, _Args...)> {using type = _Tp;};template <class _G, class _R, class _Tp, class... _Args>struct first_arg<_R (_G::*)(_Tp, _Args...) const> {using type = _Tp;};template <class _Tp, class = void> struct parse_compare : first_arg<_Tp> {};template <class _Tp>struct parse_compare<_Tp, std::__void_t<decltype(&_Tp::operator())>>: first_arg<decltype(&_Tp::operator())> {};} // namespace workspace#line 7 "Library\\src\\utils\\compare.hpp"#if __cplusplus >= 201703Lnamespace workspace {/*** @brief Compare 2 points by their value of `atan2`.** @return*/template <class _Tp>bool compare_arg(const _Tp& __p1, const _Tp& __p2) noexcept {const auto& [__x1, __y1] = __p1;const auto& [__x2, __y2] = __p2;using value_type = std::decay_t<decltype(__x1)>;using mul_type = typename multiplicable<value_type>::type;if (__y1 == value_type(0))return value_type(0) <= __x1 &&(value_type(0) < __y2 ||(__y2 == value_type(0) && __x2 < value_type(0)));return value_type(0) < __y1? value_type(0) <= __y2 &&mul_type(__y1) * __x2 < mul_type(__x1) * __y2: value_type(0) <= __y2 ||mul_type(__y1) * __x2 < mul_type(__x1) * __y2;}} // namespace workspace#endif#line 6 "Library\\lib\\utils"// #include "src/utils/fixed_point.hpp"// #include "src/utils/hash.hpp"#line 2 "Library\\src\\utils\\io\\istream.hpp"/*** @file istream.hpp* @brief Input Stream*/#include <cxxabi.h>#line 13 "Library\\src\\utils\\io\\istream.hpp"#line 16 "Library\\src\\utils\\io\\istream.hpp"namespace workspace {namespace _istream_impl {template <class _Tp, typename = void> struct helper {helper(std::istream &__is, _Tp &__x) {if _CXX17_CONSTEXPR (has_begin<_Tp &>::value)for (auto &&__e : __x) helper<std::decay_t<decltype(__e)>>(__is, __e);elsestatic_assert(has_begin<_Tp>::value, "istream unsupported type.");}};template <class _Tp>struct helper<_Tp, std::__void_t<decltype(std::declval<std::istream &>() >>std::declval<_Tp &>())>> {helper(std::istream &__is, _Tp &__x) { __is >> __x; }};#ifdef __SIZEOF_INT128__template <> struct helper<__uint128_t, void> {helper(std::istream &__is, __uint128_t &__x) {std::string __s;__is >> __s;bool __neg = false;if (__s.front() == '-') __neg = true, __s.erase(__s.begin());__x = 0;for (char __d : __s) {__x *= 10;__d -= '0';if (__neg)__x -= __d;else__x += __d;}}};template <> struct helper<__int128_t, void> {helper(std::istream &__is, __int128_t &__x) {std::string __s;__is >> __s;bool __neg = false;if (__s.front() == '-') __neg = true, __s.erase(__s.begin());__x = 0;for (char __d : __s) {__x *= 10;__d -= '0';if (__neg)__x -= __d;else__x += __d;}}};#endif // INT128template <class _T1, class _T2> struct helper<std::pair<_T1, _T2>> {helper(std::istream &__is, std::pair<_T1, _T2> &__x) {helper<_T1>(__is, __x.first), helper<_T2>(__is, __x.second);}};template <class... _Tp> struct helper<std::tuple<_Tp...>> {helper(std::istream &__is, std::tuple<_Tp...> &__x) { iterate(__is, __x); }private:template <class _Tuple, size_t _Nm = 0>void iterate(std::istream &__is, _Tuple &__x) {if _CXX17_CONSTEXPR (_Nm != std::tuple_size<_Tuple>::value) {helper<typename std::tuple_element<_Nm, _Tuple>::type>(__is, std::get<_Nm>(__x)),iterate<_Tuple, _Nm + 1>(__is, __x);}}};} // namespace _istream_impl/*** @brief A wrapper class for std::istream.*/class istream : public std::istream {public:/*** @brief Wrapped operator.*/template <typename _Tp> istream &operator>>(_Tp &__x) {_istream_impl::helper<_Tp>(*this, __x);if (std::istream::fail()) {static auto once = atexit([] {std::cerr << "\n\033[43m\033[30mwarning: failed to read \'"<< abi::__cxa_demangle(typeid(_Tp).name(), 0, 0, 0)<< "\'.\033[0m\n\n";});assert(!once);}return *this;}};decltype(auto) cin = static_cast<istream &>(std::cin);} // namespace workspace#line 9 "Library\\lib\\utils"// #include "src/utils/io/ostream.hpp"// #include "src/utils/io/read.hpp"#line 2 "Library\\src\\utils\\grid\\motion.hpp"/*** @file motion.hpp* @brief Motion*/#line 9 "Library\\src\\utils\\grid\\motion.hpp"#line 11 "Library\\src\\utils\\grid\\motion.hpp"namespace workspace {/*** @brief Transpose.* @param __grid*/template <class _Grid,typename = decltype(std::declval<std::decay_t<_Grid>>()[0].resize(0))>constexpr decltype(auto) transpose(_Grid &&__grid) noexcept {#if __cplusplus < 201703Lauto __h = __grid.size(), __w = __grid[0].size();#elseauto __h = std::size(__grid), __w = std::size(__grid[0]);#endifstd::decay_t<_Grid> __t(__w);for (auto &&__r : __t) __r.resize(__h);for (size_t __i = 0; __i != __h; ++__i)for (size_t __j = 0; __j != __w; ++__j)if _CXX17_CONSTEXPR (std::is_rvalue_reference<decltype(__grid)>::value)__t[__j][__i] = std::move(__grid[__i][__j]);else__t[__j][__i] = __grid[__i][__j];return __t;}/*** @brief Transpose.* @param __grid*/template <class _Tp, size_t _Rows, size_t _Cols>constexpr decltype(auto) transpose(const _Tp (&__grid)[_Rows][_Cols]) noexcept {std::array<std::array<_Tp, _Rows>, _Cols> __t;for (size_t __i = 0; __i != _Rows; ++__i)for (size_t __j = 0; __j != _Cols; ++__j) __t[__j][__i] = __grid[__i][__j];return __t;}/*** @brief Transpose.* @param __grid*/template <class _Tp, size_t _Rows, size_t _Cols>constexpr decltype(auto) transpose(_Tp(&&__grid)[_Rows][_Cols]) noexcept {std::array<std::array<_Tp, _Rows>, _Cols> __t;for (size_t __i = 0; __i != _Rows; ++__i)for (size_t __j = 0; __j != _Cols; ++__j)__t[__j][__i] = std::move(__grid[__i][__j]);return __t;}/*** @brief Transpose.* @param __grid*/template <class _Tp, size_t _Rows, size_t _Cols>constexpr decltype(auto) transpose(const std::array<std::array<_Tp, _Cols>, _Rows> &__grid) noexcept {std::array<std::array<_Tp, _Rows>, _Cols> __t;for (size_t __i = 0; __i != _Rows; ++__i)for (size_t __j = 0; __j != _Cols; ++__j) __t[__j][__i] = __grid[__i][__j];return __t;}/*** @brief Transpose.* @param __grid*/template <class _Tp, size_t _Rows, size_t _Cols>constexpr decltype(auto) transpose(std::array<std::array<_Tp, _Cols>, _Rows> &&__grid) noexcept {std::array<std::array<_Tp, _Rows>, _Cols> __t;for (size_t __i = 0; __i != _Rows; ++__i)for (size_t __j = 0; __j != _Cols; ++__j)__t[__j][__i] = std::move(__grid[__i][__j]);return __t;}/*** @brief Roll the grid counter-clockwise.* @param __grid*/template <class _Grid> decltype(auto) roll_ccw(_Grid &&__grid) noexcept {if _CXX17_CONSTEXPR (std::is_rvalue_reference<decltype(__grid)>::value) {auto __t = transpose(std::move(__grid));std::reverse(std::begin(__t), std::end(__t));return __t;} else {auto __t = transpose(__grid);std::reverse(std::begin(__t), std::end(__t));return __t;}}/*** @brief Roll the grid clockwise.* @param __grid*/template <class _Grid> decltype(auto) roll_cw(_Grid &&__grid) noexcept {if _CXX17_CONSTEXPR (std::is_rvalue_reference<decltype(__grid)>::value) {std::reverse(std::begin(__grid), std::end(__grid));return transpose(std::move(__grid));} else {auto __t = transpose(__grid);for (auto &&__r : __t) std::reverse(std::begin(__r), std::end(__r));return __t;}}} // namespace workspace#line 2 "Library\\src\\utils\\io\\setup.hpp"/*** @file setup.hpp* @brief I/O Setup*/#line 10 "Library\\src\\utils\\io\\setup.hpp"namespace workspace {/*** @brief Setup I/O.* @param __n Standard output precision*/void io_setup(int __n) {std::cin.tie(0)->sync_with_stdio(0);std::cout << std::fixed << std::setprecision(__n);#ifdef _buffer_checkatexit([] {char bufc;if (std::cin >> bufc)std::cerr << "\n\033[43m\033[30mwarning: buffer not empty.\033[0m\n\n";});#endif}} // namespace workspace#line 2 "Library\\src\\utils\\iterator\\category.hpp"/** @file category.hpp* @brief Iterator Category*/#line 10 "Library\\src\\utils\\iterator\\category.hpp"namespace workspace {/** @tparam Tuple Tuple of iterator types*/template <class Tuple, size_t N = std::tuple_size<Tuple>::value - 1>struct common_iterator_category {using type = typename std::common_type<typename common_iterator_category<Tuple, N - 1>::type,typename std::iterator_traits<typename std::tuple_element<N, Tuple>::type>::iterator_category>::type;};template <class Tuple> struct common_iterator_category<Tuple, 0> {using type = typename std::iterator_traits<typename std::tuple_element<0, Tuple>::type>::iterator_category;};} // namespace workspace#line 2 "Library\\src\\utils\\iterator\\reverse.hpp"/** @file reverse_iterator.hpp* @brief Reverse Iterator*/#if __cplusplus >= 201703L#include <iterator>#include <optional>namespace workspace {/** @class reverse_iterator* @brief Wrapper class for `std::reverse_iterator`.* @see http://gcc.gnu.org/PR51823*/template <class Iterator>class reverse_iterator : public std::reverse_iterator<Iterator> {using base_std = std::reverse_iterator<Iterator>;std::optional<typename base_std::value_type> deref;public:using base_std::reverse_iterator;constexpr typename base_std::reference operator*() noexcept {if (!deref) {Iterator tmp = base_std::current;deref = *--tmp;}return deref.value();}constexpr reverse_iterator &operator++() noexcept {base_std::operator++();deref.reset();return *this;}constexpr reverse_iterator &operator--() noexcept {base_std::operator++();deref.reset();return *this;}constexpr reverse_iterator operator++(int) noexcept {base_std::operator++();deref.reset();return *this;}constexpr reverse_iterator operator--(int) noexcept {base_std::operator++();deref.reset();return *this;}};} // namespace workspace#endif#line 2 "Library\\src\\utils\\make_vector.hpp"/*** @file make_vector.hpp* @brief Multi-dimensional Vector*/#if __cplusplus >= 201703L#include <tuple>#include <vector>namespace workspace {/*** @brief Make a multi-dimensional vector.** @param __dim Dimension* @param __x Initial value*/template <typename _Tp, class _Dim, size_t _Nm>constexpr decltype(auto) make_vector([[maybe_unused]] _Dim* __dim,const _Tp& __x = _Tp()) {static_assert(std::is_convertible<_Dim, size_t>::value);if constexpr (_Nm)return std::vector(*__dim,make_vector<_Tp, _Dim, _Nm - 1>(std::next(__dim), __x));elsereturn __x;}/*** @brief Make a multi-dimensional vector.** @param __dim Dimension* @param __x Initial value*/template <typename _Tp, class _Dim, size_t _Nm>constexpr decltype(auto) make_vector(const _Dim (&__dim)[_Nm],const _Tp& __x = _Tp()) {return make_vector<_Tp, _Dim, _Nm>((_Dim*)__dim, __x);}/*** @brief Make a multi-dimensional vector.** @param __dim Dimension* @param __x Initial value*/template <typename _Tp, class _Dim, size_t _Nm = 0>constexpr decltype(auto) make_vector([[maybe_unused]] const _Dim& __dim,const _Tp& __x = _Tp()) {if constexpr (_Nm == std::tuple_size<_Dim>::value)return __x;else {static_assert(std::is_convertible<std::tuple_element_t<_Nm, _Dim>, size_t>::value);return std::vector(std::get<_Nm>(__dim),make_vector<_Tp, _Dim, _Nm + 1>(__dim, __x));}}} // namespace workspace#endif#line 16 "Library\\lib\\utils"// #include "src/utils/py-like/enumerate.hpp"#line 2 "Library\\src\\utils\\py-like\\range.hpp"/*** @file range.hpp* @brief Range*/#line 9 "Library\\src\\utils\\py-like\\range.hpp"#line 2 "Library\\src\\utils\\py-like\\reversed.hpp"/*** @file reversed.hpp* @brief Reversed*/#include <initializer_list>#line 10 "Library\\src\\utils\\py-like\\reversed.hpp"namespace workspace {namespace _reversed_impl {template <class _Container> class reversed {_Container __cont;public:constexpr reversed(_Container &&__cont) noexcept : __cont(__cont) {}constexpr decltype(auto) begin() noexcept { return std::rbegin(__cont); }constexpr decltype(auto) begin() const noexcept {return std::rbegin(__cont);}constexpr decltype(auto) end() noexcept { return std::rend(__cont); }constexpr decltype(auto) end() const noexcept { return std::rend(__cont); }constexpr decltype(auto) size() const noexcept {return#if __cplusplus < 201703L__cont.size();#elsestd::size(__cont);#endif}};} // namespace _reversed_impltemplate <class _Container>constexpr decltype(auto) reversed(_Container &&__cont) noexcept {return _reversed_impl::reversed<_Container>{std::forward<_Container>(__cont)};}template <class _Tp>constexpr decltype(auto) reversed(std::initializer_list<_Tp> &&__cont) noexcept {return _reversed_impl::reversed<std::initializer_list<_Tp>>{std::forward<std::initializer_list<_Tp>>(__cont)};}} // namespace workspace#line 12 "Library\\src\\utils\\py-like\\range.hpp"#if __cplusplus >= 201703Lnamespace workspace {template <class _Index> class range {_Index __first, __last;public:class iterator {_Index current;public:using difference_type = std::ptrdiff_t;using value_type = _Index;using reference = typename std::add_const<_Index>::type &;using pointer = iterator;using iterator_category = std::random_access_iterator_tag;constexpr iterator(const _Index &__i = _Index()) noexcept : current(__i) {}constexpr bool operator==(const iterator &__x) const noexcept {return current == __x.current;}constexpr bool operator!=(const iterator &__x) const noexcept {return current != __x.current;}constexpr bool operator<(const iterator &__x) const noexcept {return current < __x.current;}constexpr bool operator<=(const iterator &__x) const noexcept {return current <= __x.current;}constexpr bool operator>(const iterator &__x) const noexcept {return current > __x.current;}constexpr bool operator>=(const iterator &__x) const noexcept {return current >= __x.current;}constexpr iterator &operator++() noexcept {++current;return *this;}constexpr iterator &operator++(int) noexcept {auto __tmp = *this;++current;return __tmp;}constexpr iterator &operator--() noexcept {--current;return *this;}constexpr iterator &operator--(int) noexcept {auto __tmp = *this;--current;return __tmp;}constexpr difference_type operator-(const iterator &__x) const noexcept {return current - __x.current;}constexpr iterator &operator+=(difference_type __x) noexcept {current += __x;return *this;}constexpr iterator operator+(difference_type __x) const noexcept {return iterator(*this) += __x;}constexpr iterator &operator-=(difference_type __x) noexcept {current -= __x;return *this;}constexpr iterator operator-(difference_type __x) const noexcept {return iterator(*this) -= __x;}constexpr reference operator*() const noexcept { return current; }};constexpr range(_Index __first, _Index __last) noexcept: __first(__first), __last(__last) {}constexpr range(_Index __last) noexcept : __first(), __last(__last) {}constexpr iterator begin() const noexcept { return iterator{__first}; }constexpr iterator end() const noexcept { return iterator{__last}; }constexpr reverse_iterator<iterator> rbegin() const noexcept {return reverse_iterator<iterator>(end());}constexpr reverse_iterator<iterator> rend() const noexcept {return reverse_iterator<iterator>(begin());}constexpr size_t size() const noexcept {return std::distance(__first, __last);}};template <class... _Args>constexpr decltype(auto) rrange(_Args &&...__args) noexcept {return reversed(range(std::forward<_Args>(__args)...));}template <class _Container>constexpr decltype(auto) iterate(_Container &&__cont) noexcept {return range(std::begin(__cont), std::end(__cont));}template <class _Container>constexpr decltype(auto) riterate(_Container &&__cont) noexcept {return range(std::rbegin(__cont), std::rend(__cont));}} // namespace workspace#endif#line 18 "Library\\lib\\utils"// #include "src/utils/py-like/reversed.hpp"// #include "src/utils/py-like/zip.hpp"#line 2 "Library\\src\\utils\\rand\\rng.hpp"/*** @file rng.hpp* @brief Random Number Generator*/#line 9 "Library\\src\\utils\\rand\\rng.hpp"namespace workspace {template <typename _Arithmetic>using uniform_distribution = typename std::conditional<std::is_integral<_Arithmetic>::value,std::uniform_int_distribution<_Arithmetic>,std::uniform_real_distribution<_Arithmetic>>::type;template <typename _Arithmetic, class _Engine = std::mt19937>class random_number_generator : uniform_distribution<_Arithmetic> {using base = uniform_distribution<_Arithmetic>;_Engine __engine;public:random_number_generator(_Arithmetic __min, _Arithmetic __max): base(__min, __max), __engine(std::random_device{}()) {}random_number_generator(_Arithmetic __max = 1): random_number_generator(0, __max) {}random_number_generator(typename base::param_type const& __param): base(__param), __engine(std::random_device{}()) {}decltype(auto) operator()() noexcept { return base::operator()(__engine); }};} // namespace workspace#line 2 "Library\\src\\utils\\rand\\shuffle.hpp"/*** @file shuffle.hpp* @brief Shuffle*/#line 10 "Library\\src\\utils\\rand\\shuffle.hpp"namespace workspace {template <class _RAIter, class _Engine = std::mt19937>void shuffle(_RAIter __first, _RAIter __last) {static _Engine __engine(std::random_device{}());std::shuffle(__first, __last, __engine);}} // namespace workspace#line 2 "Library\\src\\utils\\round_div.hpp"/** @file round_div.hpp* @brief Round Integer Division*/#line 9 "Library\\src\\utils\\round_div.hpp"#line 11 "Library\\src\\utils\\round_div.hpp"namespace workspace {/** @fn floor_div* @brief floor of fraction.* @param x the numerator* @param y the denominator* @return maximum integer z s.t. z <= x / y* @note y must be nonzero.*/template <typename T1, typename T2>constexpr typename std::enable_if<(is_integral_ext<T1>::value &&is_integral_ext<T2>::value),typename std::common_type<T1, T2>::type>::typefloor_div(T1 x, T2 y) {assert(y != 0);if (y < 0) x = -x, y = -y;return x < 0 ? (x - y + 1) / y : x / y;}/** @fn ceil_div* @brief ceil of fraction.* @param x the numerator* @param y the denominator* @return minimum integer z s.t. z >= x / y* @note y must be nonzero.*/template <typename T1, typename T2>constexpr typename std::enable_if<(is_integral_ext<T1>::value &&is_integral_ext<T2>::value),typename std::common_type<T1, T2>::type>::typeceil_div(T1 x, T2 y) {assert(y != 0);if (y < 0) x = -x, y = -y;return x < 0 ? x / y : (x + y - 1) / y;}} // namespace workspace#line 23 "Library\\lib\\utils"// #include "src\utils\rand\tree.hpp"// #include "src\utils\reference_list.hpp"#line 11 "other-workspace\\y.cc"signed main() {using namespace workspace;io_setup(15);/* givencase_info.read(); //*//* unspecifiedcase_info.total = -1; //*/return case_info.iterate();}#line 2 "Library\\src\\graph\\directed\\strongly_connected_components.hpp"/*** @file strongly_connected_component.hpp* @brief Strongly Connected Component Algorithm*/#line 12 "Library\\src\\graph\\directed\\strongly_connected_components.hpp"namespace workspace {class strongly_connected_component {public:using size_type = std::size_t;protected:std::vector<std::vector<size_type>> __graph, __dag;std::vector<size_type> __low;bool made() const { return !__low.empty(); }/*** @param src Vertex* @param c Counter* @param ptr Pointer to a stack* @param used Negative indexed* @return Low-link number of the vertex.*/size_type affix(size_type src, size_type &c, size_type *&ptr,bool *const used) {if (__low[src]) return __low[src];const size_type idx = ++c;__low[src] = idx;*ptr++ = src;for (const size_type dst : __graph[src])__low[src] = std::min(__low[src], affix(dst, c, ptr, used));if (__low[src] == idx) {__dag.push_back({});const size_type ccnt = __dag.size();used[-ccnt] = true;size_type *srcp = ptr;do __low[*--srcp] = -ccnt;while (*srcp != src);while (ptr != srcp) {const size_type now = *--ptr;for (const size_type dst : __graph[now]) {if (!used[(int)__low[dst]]) {__dag.back().emplace_back(__low[dst]);used[(int)__low[dst]] = true;}}}for (const size_type dst : __dag.back()) used[dst] = false;used[-ccnt] = false;return idx;}return __low[src];}public:strongly_connected_component() = default;strongly_connected_component(size_type __n) : __graph(__n) {}size_type add_node() {__graph.emplace_back();return __graph.size() - 1;}std::vector<size_type> add_nodes(size_type __n) {std::vector<size_type> __nds(__n);std::iota(__nds.begin(), __nds.end(), size());__graph.resize(size() + __n);return __nds;}/*** @brief Add an edge.* @param src Source* @param dst Destination*/void add_edge(size_type src, size_type dst) {assert(src < size());assert(dst < size());__graph[src].emplace_back(dst);}/*** @return Number of components.*/size_type count() {assert(made());return __dag.size();}/*** @return Number of vertices.*/size_type size() const { return __graph.size(); }/*** @param v Vertex* @return Component including given vertex.*/size_type operator[](size_type v) {assert(made());return __low[v];}const auto &graph() const { return __graph; }/*** @return Directed Acyclic Graph consisting of components.*/const auto &shrinked_dag() {assert(made());return __dag;}/*** @brief Run SCC decomposition in linear time.*/void make() {__low.assign(size(), 0);__dag.clear();size_type *ptr = new size_type[size()];bool *const used = new bool[size()];for (size_type v{}, c{}; v != size(); ++v) affix(v, c, ptr, used + size());delete[] ptr;delete[] used;for (auto &e : __low) e += __dag.size();reverse(begin(__dag), end(__dag));for (auto &arcs : __dag)for (auto &dst : arcs) dst += __dag.size();}};} // namespace workspace#line 27 "other-workspace\\y.cc"namespace workspace {void main() {// start here!int n, m;cin >> n >> m;strongly_connected_component scc(n);vector<vector<int>> ud(n);while (m--) {int a, b;cin >> a >> b;--a, --b;ud[a].emplace_back(b);ud[b].emplace_back(a);scc.add_edge(a, b);}scc.make();vector<int> checked(n);vector<pair<i32, i32>> ans;for (auto src : range(n)) {if (checked[src]) continue;queue<int> Q;Q.emplace(src);vector<int> seq;while (!Q.empty()) {src = Q.front();Q.pop();if (checked[src]) {continue;}seq.emplace_back(src);checked[src] = 1;for (auto &&to : ud[src]) {Q.emplace(to);}}sort(begin(seq), end(seq), [&](auto u, auto v) { return scc[u] < scc[v]; });for (auto i : iterate(seq)) {if (i != seq.begin()) {ans.emplace_back(*(i - 1), *i);}}unordered_set<int> comp;for (auto &&v : seq) {if (comp.count(scc[v])) {ans.emplace_back(seq.back(), seq.front());break;}comp.emplace(scc[v]);}}cout << ans.size() << "\n";for (auto &&[x, y] : ans) {++x, ++y;cout << x << " " << y << "\n";}}} // namespace workspace