結果
| 問題 | No.583 鉄道同好会 |
| ユーザー |
 taotao54321
|
| 提出日時 | 2019-04-18 22:01:59 |
| 言語 | C++17 (gcc 12.3.0 + boost 1.83.0) |
| 結果 |
AC
|
| 実行時間 | 249 ms / 2,000 ms |
| コード長 | 52,193 bytes |
| コンパイル時間 | 4,087 ms |
| コンパイル使用メモリ | 229,436 KB |
| 実行使用メモリ | 8,308 KB |
| 最終ジャッジ日時 | 2023-10-23 16:24:37 |
| 合計ジャッジ時間 | 6,421 ms |
|
ジャッジサーバーID （参考情報） |
judge15 / judge11 |
（要ログイン）
テストケース
テストケース表示| 入力 | 結果 | 実行時間 実行使用メモリ |
|---|---|---|
| testcase_00 | AC | 2 ms
4,348 KB |
| testcase_01 | AC | 2 ms
4,348 KB |
| testcase_02 | AC | 3 ms
4,348 KB |
| testcase_03 | AC | 2 ms
4,348 KB |
| testcase_04 | AC | 8 ms
5,488 KB |
| testcase_05 | AC | 2 ms
4,348 KB |
| testcase_06 | AC | 2 ms
4,348 KB |
| testcase_07 | AC | 3 ms
4,348 KB |
| testcase_08 | AC | 2 ms
4,348 KB |
| testcase_09 | AC | 2 ms
4,348 KB |
| testcase_10 | AC | 6 ms
5,496 KB |
| testcase_11 | AC | 16 ms
5,496 KB |
| testcase_12 | AC | 23 ms
5,492 KB |
| testcase_13 | AC | 23 ms
5,492 KB |
| testcase_14 | AC | 23 ms
5,492 KB |
| testcase_15 | AC | 23 ms
5,492 KB |
| testcase_16 | AC | 46 ms
5,492 KB |
| testcase_17 | AC | 50 ms
5,496 KB |
| testcase_18 | AC | 249 ms
8,308 KB |
ソースコード
/**
*
*/
// header {{{
#include <bits/stdc++.h>
using namespace std;
using i8 = int8_t;
using u8 = uint8_t;
using i16 = int16_t;
using u16 = uint16_t;
using i32 = int32_t;
using u32 = uint32_t;
using i64 = int64_t;
using u64 = uint64_t;
#ifdef __SIZEOF_INT128__
using i128 = __int128;
using u128 = unsigned __int128;
#endif
using f32 = float;
using f64 = double;
using f80 = __float80;
using f128 = __float128;
// }}}
template<typename T> constexpr T PROCON_INF();
template<> constexpr i64 PROCON_INF<i64>() { return 1'010'000'000'000'000'000LL; }
template<> constexpr f64 PROCON_INF<f64>() { return 1e100; }
constexpr i64 INF = PROCON_INF<i64>();
constexpr f64 FINF = PROCON_INF<f64>();
constexpr i64 MOD = 1'000'000'007LL;
constexpr f64 EPS = 1e-12;
constexpr f64 PI = 3.14159265358979323846;
// util {{{
#define FOR(i, start, end) for(i64 i = (start), i##_end=(end); i < i##_end; ++i)
#define REP(i, n) FOR(i, 0, n)
#define ALL(f,c,...) (([&](decltype((c)) cccc) { return (f)(std::begin(cccc), std::end(cccc), ## __VA_ARGS__); })(c))
#define SLICE(f,c,l,r,...) (([&](decltype((c)) cccc, decltype((l)) llll, decltype((r)) rrrr) {\
auto iiii = llll <= rrrr ? std::begin(cccc)+llll : std::end(cccc);\
auto jjjj = llll <= rrrr ? std::begin(cccc)+rrrr : std::end(cccc);\
return (f)(iiii, jjjj, ## __VA_ARGS__);\
})(c,l,r))
#define GENERIC(f) ([](auto&&... args) -> decltype(auto) { return (f)(std::forward<decltype(args)>(args)...); })
// BoolArray {{{
class BoolArray {
public:
using value_type = bool;
using reference = value_type&;
using const_reference = const value_type&;
using iterator = value_type*;
using const_iterator = const value_type*;
using difference_type = ptrdiff_t;
using size_type = size_t;
using reverse_iterator = std::reverse_iterator<iterator>;
using const_reverse_iterator = std::reverse_iterator<const_iterator>;
BoolArray() : BoolArray(0) {}
explicit BoolArray(size_t n) : BoolArray(n,false) {}
BoolArray(size_t n, bool value) : size_(n), data_(new bool[n]) {
ALL(fill, *this, value);
}
BoolArray(initializer_list<bool> init) : size_(init.size()), data_(new bool[size_]) {
ALL(copy, init, begin());
}
template<typename InputIt>
BoolArray(InputIt first, InputIt last) {
deque<bool> tmp(first, last);
size_ = tmp.size();
data_ = new bool[size_];
ALL(copy, tmp, begin());
}
BoolArray(const BoolArray& other) : size_(other.size_), data_(new bool[size_]) {
ALL(copy, other, begin());
}
BoolArray(BoolArray&& other) noexcept : size_(other.size_), data_(other.data_) {
other.data_ = nullptr;
}
BoolArray& operator=(const BoolArray& other) {
if(this == &other) return *this;
if(!data_ || size_ < other.size_) {
delete[] data_;
data_ = new bool[other.size_];
}
size_ = other.size_;
ALL(copy, other, begin());
return *this;
}
BoolArray& operator=(BoolArray&& other) noexcept {
if(this == &other) return *this;
size_ = other.size_;
data_ = other.data_;
other.data_ = nullptr;
}
BoolArray& operator=(initializer_list<bool> init) {
if(!data_ || size_ < init.size()) {
delete[] data_;
data_ = new bool[init.size()];
}
size_ = init.size();
ALL(copy, init, begin());
return *this;
}
void swap(BoolArray& other) noexcept {
std::swap(size_, other.size_);
std::swap(data_, other.data_);
}
~BoolArray() {
delete[] data_;
data_ = nullptr;
}
bool empty() const noexcept { return size_ == 0; }
size_type size() const noexcept { return size_; }
size_type max_size() const noexcept { return 1'010'000'000; }
iterator begin() noexcept { return data_; }
const_iterator begin() const noexcept { return data_; }
const_iterator cbegin() const noexcept { return data_; }
iterator end() noexcept { return data_+size_; }
const_iterator end() const noexcept { return data_+size_; }
const_iterator cend() const noexcept { return data_+size_; }
reverse_iterator rbegin() noexcept { return reverse_iterator(end()); }
const_reverse_iterator rbegin() const noexcept { return const_reverse_iterator(end()); }
const_reverse_iterator crbegin() const noexcept { return const_reverse_iterator(end()); }
reverse_iterator rend() noexcept { return reverse_iterator(begin()); }
const_reverse_iterator rend() const noexcept { return const_reverse_iterator(begin()); }
const_reverse_iterator crend() const noexcept { return const_reverse_iterator(begin()); }
reference operator[](size_type pos) { return data_[pos]; }
const_reference operator[](size_type pos) const { return data_[pos]; }
bool* data() noexcept { return data_; }
const bool* data() const noexcept { return data_; }
private:
size_t size_;
bool* data_;
};
void swap(BoolArray& lhs, BoolArray& rhs) noexcept { lhs.swap(rhs); }
bool operator==(const BoolArray& lhs, const BoolArray& rhs) {
return equal(begin(lhs), end(lhs), begin(rhs), end(rhs));
}
bool operator!=(const BoolArray& lhs, const BoolArray& rhs) { return !(lhs == rhs); }
bool operator<(const BoolArray& lhs, const BoolArray& rhs) {
return lexicographical_compare(begin(lhs), end(lhs), begin(rhs), end(rhs));
}
bool operator> (const BoolArray& lhs, const BoolArray& rhs) { return rhs < lhs; }
bool operator<=(const BoolArray& lhs, const BoolArray& rhs) { return !(rhs < lhs); }
bool operator>=(const BoolArray& lhs, const BoolArray& rhs) { return !(lhs < rhs); }
// }}}
// 多次元 vector {{{
// 最内周が vector<bool> になるのを避けるための措置
template<typename T>
struct Array1Container {
using type = vector<T>;
};
template<>
struct Array1Container<bool> {
using type = BoolArray;
};
// イテレート用
template<typename T>
struct is_arrayn_container {
static constexpr bool value = false;
};
template<typename T>
struct is_arrayn_container<vector<T>> {
static constexpr bool value = true;
};
template<>
struct is_arrayn_container<BoolArray> {
static constexpr bool value = true;
};
template<typename T>
auto arrayn_make(i64 n, T x) {
using Cont = typename Array1Container<T>::type;
return Cont(n, x);
}
template<typename T, typename... Args,
enable_if_t<2 <= sizeof...(Args), nullptr_t> = nullptr>
auto arrayn_make(i64 n, Args... args) {
auto inner = arrayn_make<T>(args...);
return vector<decltype(inner)>(n, inner);
}
template<typename T, typename F>
enable_if_t<!is_arrayn_container<T>::value> arrayn_foreach(T& e, F f) {
f(e);
}
template<typename T, typename F>
enable_if_t<is_arrayn_container<T>::value> arrayn_foreach(T& ary, F f) {
for(auto& e : ary)
arrayn_foreach(e, f);
}
template<typename T, typename U>
enable_if_t<is_arrayn_container<T>::value> arrayn_fill(T& ary, const U& x) {
arrayn_foreach(ary, [&x](auto& e) { e = x; });
}
// }}}
// 多次元生配列 {{{
template<typename T, typename F>
enable_if_t<rank<T>::value==0> CARRAY_FOREACH(T& e, F f) {
f(e);
}
template<typename Array, typename F>
enable_if_t<rank<Array>::value!=0> CARRAY_FOREACH(Array& ary, F f) {
for(auto& e : ary)
CARRAY_FOREACH(e, f);
}
template<typename Array, typename U>
enable_if_t<rank<Array>::value!=0> CARRAY_FILL(Array& ary, const U& v) {
CARRAY_FOREACH(ary, [&v](auto& e) { e = v; });
}
// }}}
// メモ化ラッパー (8引数まで) {{{
template<i64 N1, typename F>
class Memoized1 {
static_assert(N1 >= 1, "");
public:
explicit Memoized1(F&& f) : f_(forward<F>(f)) {}
decltype(auto) operator()(i64 x1) const {
using R = decltype(f_(*this,x1));
static bool done[N1] {};
static R memo[N1];
if(!done[x1]) {
memo[x1] = f_(*this,x1);
done[x1] = true;
}
return memo[x1];
}
private:
const F f_;
};
template<i64 N1, i64 N2, typename F>
class Memoized2 {
static_assert(N1 >= 1 && N2 >= 1, "");
public:
explicit Memoized2(F&& f) : f_(forward<F>(f)) {}
decltype(auto) operator()(i64 x1, i64 x2) const {
using R = decltype(f_(*this,x1,x2));
static bool done[N1][N2] {};
static R memo[N1][N2];
if(!done[x1][x2]) {
memo[x1][x2] = f_(*this,x1,x2);
done[x1][x2] = true;
}
return memo[x1][x2];
}
private:
const F f_;
};
template<i64 N1, i64 N2, i64 N3, typename F>
class Memoized3 {
static_assert(N1 >= 1 && N2 >= 1 && N3 >= 1, "");
public:
explicit Memoized3(F&& f) : f_(forward<F>(f)) {}
decltype(auto) operator()(i64 x1, i64 x2, i64 x3) const {
using R = decltype(f_(*this,x1,x2,x3));
static bool done[N1][N2][N3] {};
static R memo[N1][N2][N3];
if(!done[x1][x2][x3]) {
memo[x1][x2][x3] = f_(*this,x1,x2,x3);
done[x1][x2][x3] = true;
}
return memo[x1][x2][x3];
}
private:
const F f_;
};
template<i64 N1, i64 N2, i64 N3, i64 N4, typename F>
class Memoized4 {
static_assert(N1 >= 1 && N2 >= 1 && N3 >= 1 && N4 >= 1, "");
public:
explicit Memoized4(F&& f) : f_(forward<F>(f)) {}
decltype(auto) operator()(i64 x1, i64 x2, i64 x3, i64 x4) const {
using R = decltype(f_(*this,x1,x2,x3,x4));
static bool done[N1][N2][N3][N4] {};
static R memo[N1][N2][N3][N4];
if(!done[x1][x2][x3][x4]) {
memo[x1][x2][x3][x4] = f_(*this,x1,x2,x3,x4);
done[x1][x2][x3][x4] = true;
}
return memo[x1][x2][x3][x4];
}
private:
const F f_;
};
template<i64 N1, i64 N2, i64 N3, i64 N4, i64 N5, typename F>
class Memoized5 {
static_assert(N1 >= 1 && N2 >= 1 && N3 >= 1 && N4 >= 1 && N5 >= 1, "");
public:
explicit Memoized5(F&& f) : f_(forward<F>(f)) {}
decltype(auto) operator()(i64 x1, i64 x2, i64 x3, i64 x4, i64 x5) const {
using R = decltype(f_(*this,x1,x2,x3,x4,x5));
static bool done[N1][N2][N3][N4][N5] {};
static R memo[N1][N2][N3][N4][N5];
if(!done[x1][x2][x3][x4][x5]) {
memo[x1][x2][x3][x4][x5] = f_(*this,x1,x2,x3,x4,x5);
done[x1][x2][x3][x4][x5] = true;
}
return memo[x1][x2][x3][x4][x5];
}
private:
const F f_;
};
template<i64 N1, i64 N2, i64 N3, i64 N4, i64 N5, i64 N6, typename F>
class Memoized6 {
static_assert(N1 >= 1 && N2 >= 1 && N3 >= 1 && N4 >= 1 && N5 >= 1 && N6 >= 1, "");
public:
explicit Memoized6(F&& f) : f_(forward<F>(f)) {}
decltype(auto) operator()(i64 x1, i64 x2, i64 x3, i64 x4, i64 x5, i64 x6) const {
using R = decltype(f_(*this,x1,x2,x3,x4,x5,x6));
static bool done[N1][N2][N3][N4][N5][N6] {};
static R memo[N1][N2][N3][N4][N5][N6];
if(!done[x1][x2][x3][x4][x5][x6]) {
memo[x1][x2][x3][x4][x5][x6] = f_(*this,x1,x2,x3,x4,x5,x6);
done[x1][x2][x3][x4][x5][x6] = true;
}
return memo[x1][x2][x3][x4][x5][x6];
}
private:
const F f_;
};
template<i64 N1, i64 N2, i64 N3, i64 N4, i64 N5, i64 N6, i64 N7, typename F>
class Memoized7 {
static_assert(N1 >= 1 && N2 >= 1 && N3 >= 1 && N4 >= 1 && N5 >= 1 && N6 >= 1 && N7 >= 1, "");
public:
explicit Memoized7(F&& f) : f_(forward<F>(f)) {}
decltype(auto) operator()(i64 x1, i64 x2, i64 x3, i64 x4, i64 x5, i64 x6, i64 x7) const {
using R = decltype(f_(*this,x1,x2,x3,x4,x5,x6,x7));
static bool done[N1][N2][N3][N4][N5][N6][N7] {};
static R memo[N1][N2][N3][N4][N5][N6][N7];
if(!done[x1][x2][x3][x4][x5][x6][x7]) {
memo[x1][x2][x3][x4][x5][x6][x7] = f_(*this,x1,x2,x3,x4,x5,x6,x7);
done[x1][x2][x3][x4][x5][x6][x7] = true;
}
return memo[x1][x2][x3][x4][x5][x6][x7];
}
private:
const F f_;
};
template<i64 N1, i64 N2, i64 N3, i64 N4, i64 N5, i64 N6, i64 N7, i64 N8, typename F>
class Memoized8 {
static_assert(N1 >= 1 && N2 >= 1 && N3 >= 1 && N4 >= 1 && N5 >= 1 && N6 >= 1 && N7 >= 1 && N8 >= 1, "");
public:
explicit Memoized8(F&& f) : f_(forward<F>(f)) {}
decltype(auto) operator()(i64 x1, i64 x2, i64 x3, i64 x4, i64 x5, i64 x6, i64 x7, i64 x8) const {
using R = decltype(f_(*this,x1,x2,x3,x4,x5,x6,x7,x8));
static bool done[N1][N2][N3][N4][N5][N6][N7][N8] {};
static R memo[N1][N2][N3][N4][N5][N6][N7][N8];
if(!done[x1][x2][x3][x4][x5][x6][x7][x8]) {
memo[x1][x2][x3][x4][x5][x6][x7][x8] = f_(*this,x1,x2,x3,x4,x5,x6,x7,x8);
done[x1][x2][x3][x4][x5][x6][x7][x8] = true;
}
return memo[x1][x2][x3][x4][x5][x6][x7][x8];
}
private:
const F f_;
};
template<i64 N1, typename F>
decltype(auto) MEMOIZE(F&& f) {
return Memoized1<N1,F>(forward<F>(f));
}
template<i64 N1, i64 N2, typename F>
decltype(auto) MEMOIZE(F&& f) {
return Memoized2<N1,N2,F>(forward<F>(f));
}
template<i64 N1, i64 N2, i64 N3, typename F>
decltype(auto) MEMOIZE(F&& f) {
return Memoized3<N1,N2,N3,F>(forward<F>(f));
}
template<i64 N1, i64 N2, i64 N3, i64 N4, typename F>
decltype(auto) MEMOIZE(F&& f) {
return Memoized4<N1,N2,N3,N4,F>(forward<F>(f));
}
template<i64 N1, i64 N2, i64 N3, i64 N4, i64 N5, typename F>
decltype(auto) MEMOIZE(F&& f) {
return Memoized5<N1,N2,N3,N4,N5,F>(forward<F>(f));
}
template<i64 N1, i64 N2, i64 N3, i64 N4, i64 N5, i64 N6, typename F>
decltype(auto) MEMOIZE(F&& f) {
return Memoized6<N1,N2,N3,N4,N5,N6,F>(forward<F>(f));
}
template<i64 N1, i64 N2, i64 N3, i64 N4, i64 N5, i64 N6, i64 N7, typename F>
decltype(auto) MEMOIZE(F&& f) {
return Memoized7<N1,N2,N3,N4,N5,N6,N7,F>(forward<F>(f));
}
template<i64 N1, i64 N2, i64 N3, i64 N4, i64 N5, i64 N6, i64 N7, i64 N8, typename F>
decltype(auto) MEMOIZE(F&& f) {
return Memoized8<N1,N2,N3,N4,N5,N6,N7,N8,F>(forward<F>(f));
}
// }}}
// lambda で再帰 {{{
template<typename F>
class FixPoint {
public:
explicit constexpr FixPoint(F&& f) : f_(forward<F>(f)) {}
template<typename... Args>
constexpr decltype(auto) operator()(Args&&... args) const {
return f_(*this, forward<Args>(args)...);
}
private:
const F f_;
};
template<typename F>
decltype(auto) FIX(F&& f) {
return FixPoint<F>(forward<F>(f));
}
// }}}
// tuple {{{
template<typename... TS,
enable_if_t<0 < sizeof...(TS), nullptr_t> = nullptr>
constexpr auto tuple_head(const tuple<TS...>& t) {
return get<0>(t);
}
template<typename... TS, size_t i, size_t... is>
constexpr auto tuple_tail_helper(const tuple<TS...>& t, index_sequence<i,is...>) {
return make_tuple(get<is>(t)...);
}
template<typename... TS,
enable_if_t<1 == sizeof...(TS), nullptr_t> = nullptr>
constexpr auto tuple_tail(const tuple<TS...>&) {
return make_tuple();
}
template<typename... TS,
enable_if_t<1 < sizeof...(TS), nullptr_t> = nullptr>
constexpr auto tuple_tail(const tuple<TS...>& t) {
return tuple_tail_helper(t, make_index_sequence<sizeof...(TS)>());
}
// }}}
// FST/SND {{{
template<typename T1, typename T2>
T1& FST(pair<T1,T2>& p) {
return p.first;
}
template<typename T1, typename T2>
const T1& FST(const pair<T1,T2>& p) {
return p.first;
}
template<typename T1, typename T2>
T2& SND(pair<T1,T2>& p) {
return p.second;
}
template<typename T1, typename T2>
const T2& SND(const pair<T1,T2>& p) {
return p.second;
}
template<typename... TS, enable_if_t<1 <= sizeof...(TS), nullptr_t> = nullptr>
auto& FST(tuple<TS...>& t) {
return get<0>(t);
}
template<typename... TS, enable_if_t<1 <= sizeof...(TS), nullptr_t> = nullptr>
const auto& FST(const tuple<TS...>& t) {
return get<0>(t);
}
template<typename... TS, enable_if_t<2 <= sizeof...(TS), nullptr_t> = nullptr>
auto& SND(tuple<TS...>& t) {
return get<1>(t);
}
template<typename... TS, enable_if_t<2 <= sizeof...(TS), nullptr_t> = nullptr>
const auto& SND(const tuple<TS...>& t) {
return get<1>(t);
}
// }}}
template<typename C>
i64 SIZE(const C& c) { return static_cast<i64>(c.size()); }
template<typename T, size_t N>
i64 SIZE(const T (&)[N]) { return static_cast<i64>(N); }
bool is_odd (i64 x) { return x % 2 != 0; }
bool is_even(i64 x) { return x % 2 == 0; }
template<typename T> i64 cmp(T x, T y) { return (y<x) - (x<y); }
template<typename T> i64 sgn(T x) { return cmp(x, T(0)); }
// lo:OK, hi:NG
template<typename Pred>
i64 bisect_integer(i64 lo, i64 hi, Pred pred) {
assert(lo < hi);
while(lo+1 < hi) {
i64 mid = (lo+hi) / 2;
if(pred(mid))
lo = mid;
else
hi = mid;
}
return lo;
}
template<typename Pred>
f64 bisect_real(f64 lo, f64 hi, Pred pred, i64 iter=100) {
assert(lo < hi);
REP(_, iter) {
f64 mid = (lo+hi) / 2;
if(pred(mid))
lo = mid;
else
hi = mid;
}
return lo;
}
i64 ipow(i64 x, i64 e) {
assert(e >= 0);
i64 res = 1;
REP(_, e) {
res *= x;
}
return res;
}
i64 isqrt(i64 x) {
assert(x >= 0);
i64 lo = 0;
i64 hi = min<i64>(x/2+2, 3037000500LL);
return bisect_integer(lo, hi, [x](i64 r) { return r*r <= x; });
}
// 0 <= ilog2(x) <= 62
i64 ilog2(i64 x) {
assert(x > 0);
return 63 - __builtin_clzll(x);
}
// 0 <= ilog10(x) <= 18
i64 ilog10(i64 x) {
assert(x > 0);
static constexpr i64 TABLE[18] {
9LL,
99LL,
999LL,
9999LL,
99999LL,
999999LL,
9999999LL,
99999999LL,
999999999LL,
9999999999LL,
99999999999LL,
999999999999LL,
9999999999999LL,
99999999999999LL,
999999999999999LL,
9999999999999999LL,
99999999999999999LL,
999999999999999999LL,
};
REP(i, SIZE(TABLE)) {
if(x <= TABLE[i]) return i;
}
return SIZE(TABLE);
}
// Haskell の divMod と同じ
pair<i64,i64> divmod(i64 a, i64 b) {
i64 q = a / b;
i64 r = a % b;
if((b>0 && r<0) || (b<0 && r>0)) {
--q;
r += b;
}
return {q,r};
}
i64 div_ceil(i64 a, i64 b) {
i64 q = a / b;
i64 r = a % b;
if((b>0 && r>0) || (b<0 && r<0))
++q;
return q;
}
i64 div_floor(i64 a, i64 b) {
return divmod(a,b).first;
}
i64 modulo(i64 a, i64 b) {
return divmod(a,b).second;
}
bool feq(f64 x, f64 y, f64 eps=EPS) {
return fabs(x-y) < eps;
}
template<typename T, typename U, typename Comp=less<>>
bool chmax(T& xmax, const U& x, Comp comp={}) {
if(comp(xmax, x)) {
xmax = x;
return true;
}
return false;
}
template<typename T, typename U, typename Comp=less<>>
bool chmin(T& xmin, const U& x, Comp comp={}) {
if(comp(x, xmin)) {
xmin = x;
return true;
}
return false;
}
template<typename ForwardIt, typename T, typename Comp=less<>>
ForwardIt bsearch_find(ForwardIt first, ForwardIt last, const T& x, Comp comp={}) {
auto it = lower_bound(first, last, x, comp);
if(it == last || comp(x,*it)) return last;
return it;
}
// x 未満の最後の要素
template<typename BidiIt, typename T, typename Comp=less<>>
BidiIt bsearch_lt(BidiIt first, BidiIt last, const T& x, Comp comp={}) {
auto it = lower_bound(first, last, x, comp);
if(it == first) return last;
return prev(it);
}
// x 以下の最後の要素
template<typename BidiIt, typename T, typename Comp=less<>>
BidiIt bsearch_le(BidiIt first, BidiIt last, const T& x, Comp comp={}) {
auto it = upper_bound(first, last, x, comp);
if(it == first) return last;
return prev(it);
}
// x より大きい最初の要素
template<typename BidiIt, typename T, typename Comp=less<>>
BidiIt bsearch_gt(BidiIt first, BidiIt last, const T& x, Comp comp={}) {
return upper_bound(first, last, x, comp);
}
// x 以上の最初の要素
template<typename BidiIt, typename T, typename Comp=less<>>
BidiIt bsearch_ge(BidiIt first, BidiIt last, const T& x, Comp comp={}) {
return lower_bound(first, last, x, comp);
}
template<typename InputIt>
auto SUM(InputIt first, InputIt last) {
using T = typename iterator_traits<InputIt>::value_type;
return accumulate(first, last, T());
}
template<typename ForwardIt, typename UnaryOperation>
ForwardIt transform_self(ForwardIt first, ForwardIt last, UnaryOperation op) {
return transform(first, last, first, op);
}
template<typename C>
void UNIQ(C& c) {
c.erase(ALL(unique,c), end(c));
}
template<typename BinaryFunc>
auto FLIP(BinaryFunc f) {
return [f](const auto& x, const auto& y) {
return f(y,x);
};
}
template<typename BinaryFunc, typename UnaryFunc>
auto ON(BinaryFunc bf, UnaryFunc uf) {
return [bf,uf](const auto& x, const auto& y) {
return bf(uf(x), uf(y));
};
}
template<typename F>
auto LT_ON(F f) { return ON(less<>(), f); }
template<typename F>
auto GT_ON(F f) { return ON(greater<>(), f); }
template<typename F>
auto EQ_ON(F f) { return ON(equal_to<>(), f); }
template<typename F>
auto NE_ON(F f) { return ON(not_equal_to<>(), f); }
template<typename Comp=less<>>
auto EQUIV(Comp comp={}) {
return [comp](const auto& lhs, const auto& rhs) {
return !comp(lhs,rhs) && !comp(rhs,lhs);
};
}
struct IDENTITY {
template<typename T>
constexpr T&& operator()(T&& x) const noexcept {
return forward<T>(x);
}
};
template<typename ForwardIt>
void advance_bounded(ForwardIt first, ForwardIt last, ForwardIt& it, i64 n) {
if(n > 0) {
auto bound = distance(it, last);
advance(it, min<i64>(n, bound));
}
else if(n < 0) {
auto bound = distance(it, first);
advance(it, max<i64>(n, bound));
}
}
char digit_chr(i64 n) {
return static_cast<char>('0' + n);
}
i64 digit_ord(char c) {
return c - '0';
}
char lower_chr(i64 n) {
return static_cast<char>('a' + n);
}
i64 lower_ord(char c) {
return c - 'a';
}
char upper_chr(i64 n) {
return static_cast<char>('A' + n);
}
i64 upper_ord(char c) {
return c - 'A';
}
// 出力は operator<< を直接使わず、このテンプレート経由で行う
// 提出用出力とデバッグ用出力を分けるため
template<typename T>
struct Formatter {
static ostream& write_str(ostream& out, const T& x) { return out << x; }
static ostream& write_repr(ostream& out, const T& x) { return out << x; }
};
template<typename T>
ostream& WRITE_STR(ostream& out, const T& x) {
return Formatter<T>::write_str(out, x);
}
template<typename T>
ostream& WRITE_REPR(ostream& out, const T& x) {
return Formatter<T>::write_repr(out, x);
}
template<typename InputIt>
ostream& WRITE_JOIN_STR(ostream& out, InputIt first, InputIt last, const string& sep) {
while(first != last) {
WRITE_STR(out, *first++);
if(first != last)
out << sep;
}
return out;
}
template<typename InputIt>
ostream& WRITE_JOIN_REPR(ostream& out, InputIt first, InputIt last, const string& sep) {
while(first != last) {
WRITE_REPR(out, *first++);
if(first != last)
out << sep;
}
return out;
}
template<typename InputIt>
ostream& WRITE_RANGE_STR(ostream& out, InputIt first, InputIt last) {
return WRITE_JOIN_STR(out, first, last, " ");
}
template<typename InputIt>
ostream& WRITE_RANGE_REPR(ostream& out, InputIt first, InputIt last) {
out << "[";
WRITE_JOIN_REPR(out, first, last, ", ");
out << "]";
return out;
}
template<typename T>
void FROM_STR(const string& s, T& x) {
istringstream in(s);
in >> x;
}
template<typename T>
string TO_STR(const T& x) {
ostringstream out;
WRITE_STR(out, x);
return out.str();
}
template<typename T>
string TO_REPR(const T& x) {
ostringstream out;
WRITE_REPR(out, x);
return out.str();
}
template<typename InputIt>
string RANGE_TO_STR(InputIt first, InputIt last) {
ostringstream out;
WRITE_RANGE_STR(out, first, last);
return out.str();
}
template<typename InputIt>
string RANGE_TO_REPR(InputIt first, InputIt last) {
ostringstream out;
WRITE_RANGE_REPR(out, first, last);
return out.str();
}
template<typename InputIt>
string JOIN(InputIt first, InputIt last, const string& sep) {
ostringstream out;
WRITE_JOIN_STR(out, first, last, sep);
return out.str();
}
template<>
struct Formatter<i64> {
static ostream& write_str(ostream& out, i64 x) {
return out << x;
}
static ostream& write_repr(ostream& out, i64 x) {
if(x == INF) return out << "INF";
if(x == -INF) return out << "-INF";
return out << x;
}
};
template<>
struct Formatter<f64> {
static ostream& write_str(ostream& out, f64 x) {
return out << x;
}
static ostream& write_repr(ostream& out, f64 x) {
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wfloat-equal"
if(x == FINF) return out << "FINF";
if(x == -FINF) return out << "-FINF";
#pragma GCC diagnostic pop
return out << x;
}
};
template<typename T>
struct Formatter<vector<T>> {
static ostream& write_str(ostream& out, const vector<T>& v) {
return WRITE_RANGE_STR(out, begin(v), end(v));
}
static ostream& write_repr(ostream& out, const vector<T>& v) {
out << "vector";
return WRITE_RANGE_REPR(out, begin(v), end(v));
}
};
template<>
struct Formatter<BoolArray> {
static ostream& write_str(ostream& out, const BoolArray& a) {
return WRITE_RANGE_STR(out, begin(a), end(a));
}
static ostream& write_repr(ostream& out, const BoolArray& a) {
out << "BoolArray";
return WRITE_RANGE_REPR(out, begin(a), end(a));
}
};
template<typename T1, typename T2>
struct Formatter<pair<T1,T2>> {
static ostream& write_str(ostream& out, const pair<T1,T2>& p) {
WRITE_STR(out, p.first);
out << ' ';
WRITE_STR(out, p.second);
return out;
}
static ostream& write_repr(ostream& out, const pair<T1,T2>& p) {
out << "(";
WRITE_REPR(out, p.first);
out << ",";
WRITE_REPR(out, p.second);
out << ")";
return out;
}
};
template<typename... TS>
struct Formatter<tuple<TS...>> {
template<size_t I=0, enable_if_t<I == sizeof...(TS), nullptr_t> = nullptr>
static ostream& write_str_impl(ostream& out, const tuple<TS...>&) {
return out;
}
template<size_t I=0, enable_if_t<I < sizeof...(TS), nullptr_t> = nullptr>
static ostream& write_str_impl(ostream& out, const tuple<TS...>& t) {
if(I != 0) out << ' ';
WRITE_STR(out, get<I>(t));
return write_str_impl<I+1>(out, t);
}
template<size_t I=0, enable_if_t<I == sizeof...(TS), nullptr_t> = nullptr>
static ostream& write_repr_impl(ostream& out, const tuple<TS...>&) {
if(sizeof...(TS) == 0) out << "(";
return out << ")";
}
template<size_t I=0, enable_if_t<I < sizeof...(TS), nullptr_t> = nullptr>
static ostream& write_repr_impl(ostream& out, const tuple<TS...>& t) {
if(I == 0)
out << "(";
else
out << ",";
WRITE_REPR(out, get<I>(t));
return write_repr_impl<I+1>(out, t);
}
static ostream& write_str(ostream& out, const tuple<TS...>& t) {
return write_str_impl(out, t);
}
static ostream& write_repr(ostream& out, const tuple<TS...>& t) {
return write_repr_impl(out, t);
}
};
template<typename T>
void RD(T& x) {
cin >> x;
#ifdef PROCON_LOCAL
assert(cin);
#endif
}
template<typename T>
auto RD_ARRAY(i64 n) {
auto res = arrayn_make<T>(n, T());
arrayn_foreach(res, [](T& e) { RD(e); });
return res;
}
template<typename T>
auto RD_ARRAY2(i64 h, i64 w) {
auto res = arrayn_make<T>(h,w, T());
arrayn_foreach(res, [](T& e) { RD(e); });
return res;
}
template<typename T1, typename T2>
pair<T1,T2> RD_PAIR() {
T1 x; RD(x);
T2 y; RD(y);
return { x, y };
}
template<typename... TS,
enable_if_t<0 == sizeof...(TS), nullptr_t> = nullptr>
auto RD_TUPLE() {
return make_tuple();
}
template<typename T, typename... TS>
auto RD_TUPLE() {
T x; RD(x);
return tuple_cat(make_tuple(x), RD_TUPLE<TS...>());
}
void PRINT() {}
template<typename T, typename... TS>
void PRINT(const T& x, const TS& ...args) {
WRITE_STR(cout, x);
if(sizeof...(args)) {
cout << ' ';
PRINT(args...);
}
}
template<typename... TS>
void PRINTLN(const TS& ...args) {
PRINT(args...);
cout << '\n';
}
[[noreturn]] void EXIT() {
#ifdef __OPTIMIZE__
# ifdef PROCON_LOCAL
cerr.flush();
# endif
cout.flush();
_Exit(0);
#else
exit(0);
#endif
}
template<typename T>
void DBG_IMPL(i64 line, const char* expr, const T& value) {
#ifdef PROCON_LOCAL
cerr << "[L " << line << "]: ";
cerr << expr << " = ";
WRITE_REPR(cerr, value);
cerr << "\n";
#endif
}
template<typename T, size_t N>
void DBG_CARRAY_IMPL(i64 line, const char* expr, const T (&ary)[N]) {
#ifdef PROCON_LOCAL
cerr << "[L " << line << "]: ";
cerr << expr << " = ";
WRITE_RANGE_REPR(cerr, begin(ary), end(ary));
cerr << "\n";
#endif
}
template<typename InputIt>
void DBG_RANGE_IMPL(i64 line, const char* expr1, const char* expr2, InputIt first, InputIt last) {
#ifdef PROCON_LOCAL
cerr << "[L " << line << "]: ";
cerr << expr1 << "," << expr2 << " = ";
WRITE_RANGE_REPR(cerr, first, last);
cerr << "\n";
#endif
}
#define DBG(expr) DBG_IMPL(__LINE__, #expr, (expr))
#define DBG_CARRAY(expr) DBG_CARRAY_IMPL(__LINE__, #expr, (expr))
#define DBG_RANGE(first,last) DBG_RANGE_IMPL(__LINE__, #first, #last, (first), (last))
#define PAIR make_pair
#define TUPLE make_tuple
// }}}
// init {{{
struct ProconInit {
static constexpr int IOS_PREC = 15;
static constexpr bool AUTOFLUSH = false;
ProconInit() {
cin.tie(nullptr);
ios::sync_with_stdio(false);
cout << fixed << setprecision(IOS_PREC);
#ifdef PROCON_LOCAL
cerr << fixed << setprecision(IOS_PREC);
#endif
if(AUTOFLUSH)
cout << unitbuf;
}
} PROCON_INIT;
// }}}
// container {{{
// hash {{{
template<typename T>
struct procon_hash {
size_t operator()(const T& x) const {
return hash<T>()(x);
}
};
template<typename T>
size_t procon_hash_value(const T& x) {
return procon_hash<T>()(x);
}
template<typename T>
void procon_hash_combine(size_t& seed, const T& x) {
seed ^= procon_hash_value(x) + 0x9e3779b9 + (seed<<6) + (seed>>2);
}
template<typename InputIt>
void procon_hash_range(size_t& seed, InputIt first, InputIt last) {
for(; first != last; ++first)
procon_hash_combine(seed, *first);
}
template<typename InputIt>
size_t procon_hash_range(InputIt first, InputIt last) {
size_t seed = 0;
procon_hash_range(seed, first, last);
return seed;
}
template<typename... TS, enable_if_t<0 == sizeof...(TS), nullptr_t> = nullptr>
void procon_hash_tuple(size_t&, const tuple<TS...>&) {}
template<typename... TS, enable_if_t<0 < sizeof...(TS), nullptr_t> = nullptr>
void procon_hash_tuple(size_t& seed, const tuple<TS...>& t) {
procon_hash_combine(seed, tuple_head(t));
procon_hash_tuple(seed, tuple_tail(t));
}
template<typename T>
struct procon_hash<vector<T>> {
size_t operator()(const vector<T>& v) const {
return ALL(procon_hash_range, v);
}
};
template<typename T1, typename T2>
struct procon_hash<pair<T1,T2>> {
size_t operator()(const pair<T1,T2>& p) const {
size_t seed = 0;
procon_hash_combine(seed, p.first);
procon_hash_combine(seed, p.second);
return seed;
}
};
template<typename... TS>
struct procon_hash<tuple<TS...>> {
size_t operator()(const tuple<TS...>& t) const {
size_t seed = 0;
procon_hash_tuple(seed, t);
return seed;
}
};
template<typename T, typename Eq=equal_to<T>>
using HashSet = unordered_set<T,procon_hash<T>,Eq>;
template<typename K, typename V, typename Eq=equal_to<K>>
using HashMap = unordered_map<K,V,procon_hash<K>,Eq>;
template<typename T, typename Eq=equal_to<T>>
using HashMultiset = unordered_multiset<T,procon_hash<T>,Eq>;
template<typename K, typename V, typename Eq=equal_to<K>>
using HashMultimap = unordered_multimap<K,V,procon_hash<K>,Eq>;
// }}}
template<typename T>
using MaxHeap = priority_queue<T, vector<T>, less<T>>;
template<typename T>
using MinHeap = priority_queue<T, vector<T>, greater<T>>;
// set/map/multiset/multimap search {{{
// set {{{
template<typename T, typename Comp>
auto set_search_lt(set<T,Comp>& s, const T& x) {
auto it = s.lower_bound(x);
if(it == begin(s)) return end(s);
return prev(it);
}
template<typename T, typename Comp>
auto set_search_lt(const set<T,Comp>& s, const T& x) {
auto it = s.lower_bound(x);
if(it == begin(s)) return end(s);
return prev(it);
}
template<typename T, typename Comp>
auto set_search_le(set<T,Comp>& s, const T& x) {
auto it = s.upper_bound(x);
if(it == begin(s)) return end(s);
return prev(it);
}
template<typename T, typename Comp>
auto set_search_le(const set<T,Comp>& s, const T& x) {
auto it = s.upper_bound(x);
if(it == begin(s)) return end(s);
return prev(it);
}
template<typename T, typename Comp>
auto set_search_gt(set<T,Comp>& s, const T& x) {
return s.upper_bound(x);
}
template<typename T, typename Comp>
auto set_search_gt(const set<T,Comp>& s, const T& x) {
return s.upper_bound(x);
}
template<typename T, typename Comp>
auto set_search_ge(set<T,Comp>& s, const T& x) {
return s.lower_bound(x);
}
template<typename T, typename Comp>
auto set_search_ge(const set<T,Comp>& s, const T& x) {
return s.lower_bound(x);
}
// }}}
// map {{{
template<typename K, typename V, typename Comp>
auto map_search_lt(map<K,V,Comp>& m, const K& x) {
auto it = m.lower_bound(x);
if(it == begin(m)) return end(m);
return prev(it);
}
template<typename K, typename V, typename Comp>
auto map_search_lt(const map<K,V,Comp>& m, const K& x) {
auto it = m.lower_bound(x);
if(it == begin(m)) return end(m);
return prev(it);
}
template<typename K, typename V, typename Comp>
auto map_search_le(map<K,V,Comp>& m, const K& x) {
auto it = m.upper_bound(x);
if(it == begin(m)) return end(m);
return prev(it);
}
template<typename K, typename V, typename Comp>
auto map_search_le(const map<K,V,Comp>& m, const K& x) {
auto it = m.upper_bound(x);
if(it == begin(m)) return end(m);
return prev(it);
}
template<typename K, typename V, typename Comp>
auto map_search_gt(map<K,V,Comp>& m, const K& x) {
return m.upper_bound(x);
}
template<typename K, typename V, typename Comp>
auto map_search_gt(const map<K,V,Comp>& m, const K& x) {
return m.upper_bound(x);
}
template<typename K, typename V, typename Comp>
auto map_search_ge(map<K,V,Comp>& m, const K& x) {
return m.lower_bound(x);
}
template<typename K, typename V, typename Comp>
auto map_search_ge(const map<K,V,Comp>& m, const K& x) {
return m.lower_bound(x);
}
// }}}
// multiset {{{
template<typename T, typename Comp>
auto set_search_lt(multiset<T,Comp>& s, const T& x) {
auto it = s.lower_bound(x);
if(it == begin(s)) return end(s);
return prev(it);
}
template<typename T, typename Comp>
auto set_search_lt(const multiset<T,Comp>& s, const T& x) {
auto it = s.lower_bound(x);
if(it == begin(s)) return end(s);
return prev(it);
}
template<typename T, typename Comp>
auto set_search_le(multiset<T,Comp>& s, const T& x) {
auto it = s.upper_bound(x);
if(it == begin(s)) return end(s);
return prev(it);
}
template<typename T, typename Comp>
auto set_search_le(const multiset<T,Comp>& s, const T& x) {
auto it = s.upper_bound(x);
if(it == begin(s)) return end(s);
return prev(it);
}
template<typename T, typename Comp>
auto set_search_gt(multiset<T,Comp>& s, const T& x) {
return s.upper_bound(x);
}
template<typename T, typename Comp>
auto set_search_gt(const multiset<T,Comp>& s, const T& x) {
return s.upper_bound(x);
}
template<typename T, typename Comp>
auto set_search_ge(multiset<T,Comp>& s, const T& x) {
return s.lower_bound(x);
}
template<typename T, typename Comp>
auto set_search_ge(const multiset<T,Comp>& s, const T& x) {
return s.lower_bound(x);
}
// }}}
// multimap {{{
template<typename K, typename V, typename Comp>
auto map_search_lt(multimap<K,V,Comp>& m, const K& x) {
auto it = m.lower_bound(x);
if(it == begin(m)) return end(m);
return prev(it);
}
template<typename K, typename V, typename Comp>
auto map_search_lt(const multimap<K,V,Comp>& m, const K& x) {
auto it = m.lower_bound(x);
if(it == begin(m)) return end(m);
return prev(it);
}
template<typename K, typename V, typename Comp>
auto map_search_le(multimap<K,V,Comp>& m, const K& x) {
auto it = m.upper_bound(x);
if(it == begin(m)) return end(m);
return prev(it);
}
template<typename K, typename V, typename Comp>
auto map_search_le(const multimap<K,V,Comp>& m, const K& x) {
auto it = m.upper_bound(x);
if(it == begin(m)) return end(m);
return prev(it);
}
template<typename K, typename V, typename Comp>
auto map_search_gt(multimap<K,V,Comp>& m, const K& x) {
return m.upper_bound(x);
}
template<typename K, typename V, typename Comp>
auto map_search_gt(const multimap<K,V,Comp>& m, const K& x) {
return m.upper_bound(x);
}
template<typename K, typename V, typename Comp>
auto map_search_ge(multimap<K,V,Comp>& m, const K& x) {
return m.lower_bound(x);
}
template<typename K, typename V, typename Comp>
auto map_search_ge(const multimap<K,V,Comp>& m, const K& x) {
return m.lower_bound(x);
}
// }}}
// }}}
template<typename T, typename Comp>
bool set_contains(const set<T,Comp>& s, const typename set<T,Comp>::key_type& x) {
return s.find(x) != end(s);
}
template<typename T, typename Hash, typename Eq>
bool set_contains(const unordered_set<T,Hash,Eq>& s, const typename unordered_set<T,Hash,Eq>::key_type& x) {
return s.find(x) != end(s);
}
template<typename T, typename Comp>
bool set_contains(const multiset<T,Comp>& s, const typename multiset<T,Comp>::key_type& x) {
return s.find(x) != end(s);
}
template<typename T, typename Hash, typename Eq>
bool set_contains(const unordered_multiset<T,Hash,Eq>& s, const typename unordered_multiset<T,Hash,Eq>::key_type& x) {
return s.find(x) != end(s);
}
template<typename K, typename V, typename Comp>
bool map_contains(const map<K,V,Comp>& m, const typename map<K,V,Comp>::key_type& k) {
return m.find(k) != end(m);
}
template<typename K, typename V, typename Hash, typename Eq>
bool map_contains(const unordered_map<K,V,Hash,Eq>& m, const typename unordered_map<K,V,Hash,Eq>::key_type& k) {
return m.find(k) != end(m);
}
template<typename K, typename V, typename Comp>
bool map_contains(const multimap<K,V,Comp>& m, const typename map<K,V,Comp>::key_type& k) {
return m.find(k) != end(m);
}
template<typename K, typename V, typename Hash, typename Eq>
bool map_contains(const unordered_multimap<K,V,Hash,Eq>& m, const typename unordered_map<K,V,Hash,Eq>::key_type& k) {
return m.find(k) != end(m);
}
template<typename K, typename Comp>
bool multiset_erase_one(multiset<K,Comp>& m, const typename multiset<K,Comp>::key_type& k) {
auto it = m.find(k);
if(it == end(m)) return false;
m.erase(it);
return true;
}
template<typename K, typename Hash, typename Eq>
bool multiset_erase_one(unordered_multiset<K,Hash,Eq>& m, const typename unordered_multiset<K,Hash,Eq>::key_type& k) {
auto it = m.find(k);
if(it == end(m)) return false;
m.erase(it);
return true;
}
// POP() 系 {{{
// 効率は悪い
template<typename T>
T POP_FRONT(vector<T>& v) {
T x = v.front(); v.erase(begin(v));
return x;
}
template<typename T>
T POP_BACK(vector<T>& v) {
T x = v.back(); v.pop_back();
return x;
}
template<typename T>
T POP_FRONT(deque<T>& v) {
T x = v.front(); v.pop_front();
return x;
}
template<typename T>
T POP_BACK(deque<T>& v) {
T x = v.back(); v.pop_back();
return x;
}
template<typename T>
T POP_FRONT(forward_list<T>& ls) {
T x = ls.front(); ls.pop_front();
return x;
}
template<typename T>
T POP_FRONT(list<T>& ls) {
T x = ls.front(); ls.pop_front();
return x;
}
template<typename T>
T POP_BACK(list<T>& ls) {
T x = ls.back(); ls.pop_back();
return x;
}
template<typename T, typename C>
T POP(stack<T,C>& stk) {
T x = stk.top(); stk.pop();
return x;
}
template<typename T, typename C>
T POP(queue<T,C>& que) {
T x = que.front(); que.pop();
return x;
}
template<typename T, typename C, typename Comp>
T POP(priority_queue<T,C,Comp>& que) {
T x = que.top(); que.pop();
return x;
}
// }}}
// bimap {{{
template<typename T1, typename T2>
struct BiHashMap {
HashMap<T1,T2> fwd_;
HashMap<T2,T1> rev_;
void insert(const T1& x, const T2& y) {
auto it_fwd = fwd_.find(x);
if(it_fwd == end(fwd_)) {
fwd_.insert(it_fwd, make_pair(x,y));
rev_.insert(end(rev_), make_pair(y,x));
}
else {
assert(y == it_fwd->second);
}
}
bool contains_fwd(const T1& x) const {
return map_contains(fwd_, x);
}
bool contains_rev(const T2& y) const {
return map_contains(rev_, y);
}
const T2& at_fwd(const T1& x) const {
auto it = fwd_.find(x);
assert(it != end(fwd_));
return it->second;
}
const T1& at_rev(const T2& y) const {
auto it = rev_.find(y);
assert(it != end(rev_));
return it->second;
}
size_t size() const { return fwd_.size(); }
};
// }}}
// Formatter {{{
template<typename T, size_t N>
struct Formatter<array<T,N>> {
static ostream& write_str(ostream& out, const array<T,N>& a) {
return WRITE_RANGE_STR(out, begin(a), end(a));
}
static ostream& write_repr(ostream& out, const array<T,N>& a) {
out << "array";
return WRITE_RANGE_REPR(out, begin(a), end(a));
}
};
template<typename T>
struct Formatter<deque<T>> {
static ostream& write_str(ostream& out, const deque<T>& deq) {
return WRITE_RANGE_STR(out, begin(deq), end(deq));
}
static ostream& write_repr(ostream& out, const deque<T>& deq) {
out << "deque";
return WRITE_RANGE_REPR(out, begin(deq), end(deq));
}
};
template<typename T>
struct Formatter<forward_list<T>> {
static ostream& write_str(ostream& out, const forward_list<T>& ls) {
return WRITE_RANGE_STR(out, begin(ls), end(ls));
}
static ostream& write_repr(ostream& out, const forward_list<T>& ls) {
out << "forward_list";
return WRITE_RANGE_REPR(out, begin(ls), end(ls));
}
};
template<typename T>
struct Formatter<list<T>> {
static ostream& write_str(ostream& out, const list<T>& ls) {
return WRITE_RANGE_STR(out, begin(ls), end(ls));
}
static ostream& write_repr(ostream& out, const list<T>& ls) {
out << "list";
return WRITE_RANGE_REPR(out, begin(ls), end(ls));
}
};
template<typename T, typename Comp>
struct Formatter<set<T,Comp>> {
static ostream& write_str(ostream& out, const set<T,Comp>& s) {
return WRITE_RANGE_STR(out, begin(s), end(s));
}
static ostream& write_repr(ostream& out, const set<T,Comp>& s) {
out << "set";
return WRITE_RANGE_REPR(out, begin(s), end(s));
}
};
template<typename T, typename Comp>
struct Formatter<multiset<T,Comp>> {
static ostream& write_str(ostream& out, const multiset<T,Comp>& s) {
return WRITE_RANGE_STR(out, begin(s), end(s));
}
static ostream& write_repr(ostream& out, const multiset<T,Comp>& s) {
out << "multiset";
return WRITE_RANGE_REPR(out, begin(s), end(s));
}
};
template<typename T, typename Hash, typename Eq>
struct Formatter<unordered_set<T,Hash,Eq>> {
static ostream& write_str(ostream& out, const unordered_set<T,Hash,Eq>& s) {
return WRITE_RANGE_STR(out, begin(s), end(s));
}
static ostream& write_repr(ostream& out, const unordered_set<T,Hash,Eq>& s) {
out << "unordered_set";
return WRITE_RANGE_REPR(out, begin(s), end(s));
}
};
template<typename T, typename Hash, typename Eq>
struct Formatter<unordered_multiset<T,Hash,Eq>> {
static ostream& write_str(ostream& out, const unordered_multiset<T,Hash,Eq>& s) {
return WRITE_RANGE_STR(out, begin(s), end(s));
}
static ostream& write_repr(ostream& out, const unordered_multiset<T,Hash,Eq>& s) {
out << "unordered_multiset";
return WRITE_RANGE_REPR(out, begin(s), end(s));
}
};
template<typename K, typename V, typename Comp>
struct Formatter<map<K,V,Comp>> {
static ostream& write_str(ostream& out, const map<K,V,Comp>& m) {
return WRITE_RANGE_STR(out, begin(m), end(m));
}
static ostream& write_repr(ostream& out, const map<K,V,Comp>& m) {
out << "map";
return WRITE_RANGE_REPR(out, begin(m), end(m));
}
};
template<typename K, typename V, typename Comp>
struct Formatter<multimap<K,V,Comp>> {
static ostream& write_str(ostream& out, const multimap<K,V,Comp>& m) {
return WRITE_RANGE_STR(out, begin(m), end(m));
}
static ostream& write_repr(ostream& out, const multimap<K,V,Comp>& m) {
out << "multimap";
return WRITE_RANGE_REPR(out, begin(m), end(m));
}
};
template<typename K, typename V, typename Hash, typename Eq>
struct Formatter<unordered_map<K,V,Hash,Eq>> {
static ostream& write_str(ostream& out, const unordered_map<K,V,Hash,Eq>& m) {
return WRITE_RANGE_STR(out, begin(m), end(m));
}
static ostream& write_repr(ostream& out, const unordered_map<K,V,Hash,Eq>& m) {
out << "unordered_map";
return WRITE_RANGE_REPR(out, begin(m), end(m));
}
};
template<typename K, typename V, typename Hash, typename Eq>
struct Formatter<unordered_multimap<K,V,Hash,Eq>> {
static ostream& write_str(ostream& out, const unordered_multimap<K,V,Hash,Eq>& m) {
return WRITE_RANGE_STR(out, begin(m), end(m));
}
static ostream& write_repr(ostream& out, const unordered_multimap<K,V,Hash,Eq>& m) {
out << "unordered_multimap";
return WRITE_RANGE_REPR(out, begin(m), end(m));
}
};
template<typename T, typename C>
struct Formatter<stack<T,C>> {
static ostream& write_str(ostream& out, const stack<T,C>& orig) {
stack<T,C> stk(orig);
while(!stk.empty()) {
WRITE_STR(out, stk.top()); stk.pop();
if(!stk.empty()) out << ' ';
}
return out;
}
static ostream& write_repr(ostream& out, const stack<T,C>& orig) {
stack<T,C> stk(orig);
out << "stack[";
while(!stk.empty()) {
WRITE_REPR(out, stk.top()); stk.pop();
if(!stk.empty()) out << ", ";
}
out << "]";
return out;
}
};
template<typename T, typename C>
struct Formatter<queue<T,C>> {
static ostream& write_str(ostream& out, const queue<T,C>& orig) {
queue<T,C> que(orig);
while(!que.empty()) {
WRITE_STR(out, que.front()); que.pop();
if(!que.empty()) out << ' ';
}
return out;
}
static ostream& write_repr(ostream& out, const queue<T,C>& orig) {
queue<T,C> que(orig);
out << "queue[";
while(!que.empty()) {
WRITE_REPR(out, que.front()); que.pop();
if(!que.empty()) out << ", ";
}
out << "]";
return out;
}
};
template<typename T, typename C, typename Comp>
struct Formatter<priority_queue<T,C,Comp>> {
static ostream& write_str(ostream& out, const priority_queue<T,C,Comp>& orig) {
priority_queue<T,C,Comp> que(orig);
while(!que.empty()) {
WRITE_STR(out, que.top()); que.pop();
if(!que.empty()) out << ' ';
}
return out;
}
static ostream& write_repr(ostream& out, const priority_queue<T,C,Comp>& orig) {
priority_queue<T,C,Comp> que(orig);
out << "priority_queue[";
while(!que.empty()) {
WRITE_REPR(out, que.top()); que.pop();
if(!que.empty()) out << ", ";
}
out << "]";
return out;
}
};
// }}}
// }}}
//--------------------------------------------------------------------
// 各頂点の (indegree,outdegree) のリストを返す
vector<pair<i64,i64>> graph_degrees(const vector<vector<i64>>& g) {
i64 n = SIZE(g);
vector<pair<i64,i64>> res(n, {0,0});
REP(from, n) {
for(i64 to : g[from]) {
++FST(res[from]);
++SND(res[to]);
}
}
return res;
}
// 無向グラフのオイラー路
//
// g は隣接リスト(破壊される)
// start は始点
vector<i64> graph_euler_trail_undirected(vector<vector<i64>>& g, i64 start) {
vector<i64> res;
auto dfs = FIX([&g,&res](auto self, i64 v) -> void {
while(!g[v].empty()) {
i64 to = POP_BACK(g[v]);
g[to].erase(ALL(find, g[to], v));
self(to);
}
res.emplace_back(v);
});
dfs(start);
ALL(reverse, res);
return res;
}
#if 0
// 無向グラフのオイラー路 (隣接行列版)
//
// g[v][w]: v,w 間の辺の本数 (破壊される)
// start: 始点
vector<i64> graph_euler_trail_undirected_matrix(vector<vector<i64>>& g, i64 start) {
i64 n = SIZE(g);
vector<i64> res;
auto dfs = FIX([n,&g,&res](auto&& self, i64 v) -> void {
REP(to, n) {
if(g[v][to] == 0) continue;
--g[v][to];
--g[to][v];
self(to);
}
res.emplace_back(v);
});
dfs(start);
ALL(reverse, res);
return res;
}
#endif
// 無向グラフのオイラー路 (隣接行列版)
//
// g[v][w]: v,w 間の辺の本数 (破壊される)
// start: 始点
vector<i64> graph_euler_trail_undirected_matrix(vector<vector<i64>>& g, i64 start) {
enum Action { CALL, RESUME };
i64 n = SIZE(g);
vector<i64> res;
stack<tuple<Action,i64>> stk;
stk.emplace(CALL, start);
while(!stk.empty()) {
Action act; i64 v; tie(act,v) = POP(stk);
switch(act) {
case CALL:
stk.emplace(RESUME, v);
REP(to, n) {
if(g[v][to] == 0) continue;
--g[v][to];
--g[to][v];
stk.emplace(CALL, to);
}
break;
case RESUME:
res.emplace_back(v);
break;
}
}
ALL(reverse, res);
return res;
}
// 各頂点の (indegree,outdegree) のリストを返す (隣接行列版)
vector<pair<i64,i64>> graph_degrees_matrix(const vector<vector<i64>>& g) {
i64 n = SIZE(g);
vector<pair<i64,i64>> res(n, {0,0});
REP(from, n) REP(to, n) {
i64 k = g[from][to];
SND(res[from]) += k;
FST(res[to]) += k;
}
return res;
}
[[noreturn]] void impossible() {
PRINTLN("NO");
EXIT();
}
void solve() {
i64 N; RD(N);
i64 M; RD(M);
auto G = arrayn_make<i64>(N,N, 0);
i64 v_any = -1;
REP(_, M) {
i64 s,t; RD(s); RD(t);
++G[s][t];
++G[t][s];
v_any = s;
}
auto degs = graph_degrees_matrix(G);
DBG(degs);
i64 cnt = 0;
vector<i64> odds;
REP(i, N) {
i64 d = FST(degs[i]);
if(d > 0)
++cnt;
if(is_odd(d))
odds.emplace_back(i);
}
if(!odds.empty() && SIZE(odds) != 2) impossible();
//DBG(odds);
i64 s;
if(SIZE(odds) == 2) {
s = odds.front();
}
else {
s = v_any;
}
//DBG(s);
auto trail = graph_euler_trail_undirected_matrix(G, s);
//DBG(trail);
ALL(sort, trail);
UNIQ(trail);
if(SIZE(trail) != cnt) impossible();
PRINTLN("YES");
}
signed main() {
solve();
EXIT();
}