#include #ifdef _MSC_VER # include #else # include #endif #include #include namespace suisen { // ! utility template using constraints_t = std::enable_if_t, std::nullptr_t>; template constexpr decltype(auto) constexpr_if(Then&& then, OrElse&& or_else) { if constexpr (cond_v) { return std::forward(then); } else { return std::forward(or_else); } } // ! function template using is_same_as_invoke_result = std::is_same, ReturnType>; template using is_uni_op = is_same_as_invoke_result; template using is_bin_op = is_same_as_invoke_result; template using is_comparator = std::is_same, bool>; // ! integral template >> constexpr int bit_num = std::numeric_limits>::digits; template struct is_nbit { static constexpr bool value = bit_num == n; }; template static constexpr bool is_nbit_v = is_nbit::value; // ? template struct safely_multipliable {}; template <> struct safely_multipliable { using type = long long; }; template <> struct safely_multipliable { using type = __int128_t; }; template <> struct safely_multipliable { using type = unsigned long long; }; template <> struct safely_multipliable { using type = __uint128_t; }; template <> struct safely_multipliable { using type = __uint128_t; }; template <> struct safely_multipliable { using type = float; }; template <> struct safely_multipliable { using type = double; }; template <> struct safely_multipliable { using type = long double; }; template using safely_multipliable_t = typename safely_multipliable::type; template struct rec_value_type { using type = T; }; template struct rec_value_type> { using type = typename rec_value_type::type; }; template using rec_value_type_t = typename rec_value_type::type; } // namespace suisen // ! type aliases using i128 = __int128_t; using u128 = __uint128_t; template using pq_greater = std::priority_queue, std::greater>; // ! macros (internal) #define DETAIL_OVERLOAD2(_1,_2,name,...) name #define DETAIL_OVERLOAD3(_1,_2,_3,name,...) name #define DETAIL_OVERLOAD4(_1,_2,_3,_4,name,...) name #define DETAIL_REP4(i,l,r,s) for(std::remove_reference_t>i=(l);i<(r);i+=(s)) #define DETAIL_REP3(i,l,r) DETAIL_REP4(i,l,r,1) #define DETAIL_REP2(i,n) DETAIL_REP3(i,0,n) #define DETAIL_REPINF3(i,l,s) for(std::remove_reference_t>i=(l);;i+=(s)) #define DETAIL_REPINF2(i,l) DETAIL_REPINF3(i,l,1) #define DETAIL_REPINF1(i) DETAIL_REPINF2(i,0) #define DETAIL_RREP4(i,l,r,s) for(std::remove_reference_t>i=(l)+fld((r)-(l)-1,s)*(s);i>=(l);i-=(s)) #define DETAIL_RREP3(i,l,r) DETAIL_RREP4(i,l,r,1) #define DETAIL_RREP2(i,n) DETAIL_RREP3(i,0,n) #define DETAIL_CAT_I(a, b) a##b #define DETAIL_CAT(a, b) DETAIL_CAT_I(a, b) #define DETAIL_UNIQVAR(tag) DETAIL_CAT(tag, __LINE__) // ! macros #define REP(...) DETAIL_OVERLOAD4(__VA_ARGS__, DETAIL_REP4 , DETAIL_REP3 , DETAIL_REP2 )(__VA_ARGS__) #define RREP(...) DETAIL_OVERLOAD4(__VA_ARGS__, DETAIL_RREP4 , DETAIL_RREP3 , DETAIL_RREP2 )(__VA_ARGS__) #define REPINF(...) DETAIL_OVERLOAD3(__VA_ARGS__, DETAIL_REPINF3, DETAIL_REPINF2, DETAIL_REPINF1)(__VA_ARGS__) #define LOOP(n) for (std::remove_reference_t> DETAIL_UNIQVAR(loop_variable) = n; DETAIL_UNIQVAR(loop_variable) --> 0;) #define ALL(iterable) std::begin(iterable), std::end(iterable) #define INPUT(type, ...) type __VA_ARGS__; read(__VA_ARGS__) // ! debug #ifdef LOCAL # define debug(...) debug_internal(#__VA_ARGS__, __VA_ARGS__) template void debug_internal(const char* s, T&& first, Args&&... args) { constexpr const char* prefix = "[\033[32mDEBUG\033[m] "; constexpr const char* open_brakets = sizeof...(args) == 0 ? "" : "("; constexpr const char* close_brakets = sizeof...(args) == 0 ? "" : ")"; std::cerr << prefix << open_brakets << s << close_brakets << ": " << open_brakets << std::forward(first); ((std::cerr << ", " << std::forward(args)), ...); std::cerr << close_brakets << "\n"; } #else # define debug(...) void(0) #endif // ! I/O utilities // __int128_t std::ostream& operator<<(std::ostream& dest, __int128_t value) { std::ostream::sentry s(dest); if (s) { __uint128_t tmp = value < 0 ? -value : value; char buffer[128]; char* d = std::end(buffer); do { --d; *d = "0123456789"[tmp % 10]; tmp /= 10; } while (tmp != 0); if (value < 0) { --d; *d = '-'; } int len = std::end(buffer) - d; if (dest.rdbuf()->sputn(d, len) != len) { dest.setstate(std::ios_base::badbit); } } return dest; } // __uint128_t std::ostream& operator<<(std::ostream& dest, __uint128_t value) { std::ostream::sentry s(dest); if (s) { char buffer[128]; char* d = std::end(buffer); do { --d; *d = "0123456789"[value % 10]; value /= 10; } while (value != 0); int len = std::end(buffer) - d; if (dest.rdbuf()->sputn(d, len) != len) { dest.setstate(std::ios_base::badbit); } } return dest; } // pair template std::ostream& operator<<(std::ostream& out, const std::pair& a) { return out << a.first << ' ' << a.second; } // tuple template std::ostream& operator<<(std::ostream& out, const std::tuple& a) { if constexpr (N >= std::tuple_size_v>) return out; else { out << std::get(a); if constexpr (N + 1 < std::tuple_size_v>) out << ' '; return operator<<(out, a); } } // vector template std::ostream& operator<<(std::ostream& out, const std::vector& a) { for (auto it = a.begin(); it != a.end();) { out << *it; if (++it != a.end()) out << ' '; } return out; } // array template std::ostream& operator<<(std::ostream& out, const std::array& a) { for (auto it = a.begin(); it != a.end();) { out << *it; if (++it != a.end()) out << ' '; } return out; } inline void print() { std::cout << '\n'; } template inline void print(const Head& head, const Tail &...tails) { std::cout << head; if (sizeof...(tails)) std::cout << ' '; print(tails...); } template auto print_all(const Iterable& v, std::string sep = " ", std::string end = "\n") -> decltype(std::cout << *v.begin(), void()) { for (auto it = v.begin(); it != v.end();) { std::cout << *it; if (++it != v.end()) std::cout << sep; } std::cout << end; } __int128_t stoi128(const std::string& s) { __int128_t ret = 0; for (int i = 0; i < int(s.size()); i++) if ('0' <= s[i] and s[i] <= '9') ret = 10 * ret + s[i] - '0'; if (s[0] == '-') ret = -ret; return ret; } __uint128_t stou128(const std::string& s) { __uint128_t ret = 0; for (int i = 0; i < int(s.size()); i++) if ('0' <= s[i] and s[i] <= '9') ret = 10 * ret + s[i] - '0'; return ret; } // __int128_t std::istream& operator>>(std::istream& in, __int128_t& v) { std::string s; in >> s; v = stoi128(s); return in; } // __uint128_t std::istream& operator>>(std::istream& in, __uint128_t& v) { std::string s; in >> s; v = stou128(s); return in; } // pair template std::istream& operator>>(std::istream& in, std::pair& a) { return in >> a.first >> a.second; } // tuple template std::istream& operator>>(std::istream& in, std::tuple& a) { if constexpr (N >= std::tuple_size_v>) return in; else return operator>>(in >> std::get(a), a); } // vector template std::istream& operator>>(std::istream& in, std::vector& a) { for (auto it = a.begin(); it != a.end(); ++it) in >> *it; return in; } // array template std::istream& operator>>(std::istream& in, std::array& a) { for (auto it = a.begin(); it != a.end(); ++it) in >> *it; return in; } template void read(Args &...args) { (std::cin >> ... >> args); } // ! integral utilities // Returns pow(-1, n) template constexpr inline int pow_m1(T n) { return -(n & 1) | 1; } // Returns pow(-1, n) template <> constexpr inline int pow_m1(bool n) { return -int(n) | 1; } // Returns floor(x / y) template constexpr inline T fld(const T x, const T y) { return (x ^ y) >= 0 ? x / y : (x - (y + pow_m1(y >= 0))) / y; } template constexpr inline T cld(const T x, const T y) { return (x ^ y) <= 0 ? x / y : (x + (y + pow_m1(y >= 0))) / y; } template >, std::nullptr_t> = nullptr> __attribute__((target("popcnt"))) constexpr inline int popcount(const T x) { return _mm_popcnt_u32(x); } template , std::nullptr_t> = nullptr> __attribute__((target("popcnt"))) constexpr inline int popcount(const T x) { return _mm_popcnt_u64(x); } template >, std::nullptr_t> = nullptr> constexpr inline int count_lz(const T x) { return x ? __builtin_clz(x) : suisen::bit_num; } template , std::nullptr_t> = nullptr> constexpr inline int count_lz(const T x) { return x ? __builtin_clzll(x) : suisen::bit_num; } template >, std::nullptr_t> = nullptr> constexpr inline int count_tz(const T x) { return x ? __builtin_ctz(x) : suisen::bit_num; } template , std::nullptr_t> = nullptr> constexpr inline int count_tz(const T x) { return x ? __builtin_ctzll(x) : suisen::bit_num; } template constexpr inline int floor_log2(const T x) { return suisen::bit_num - 1 - count_lz(x); } template constexpr inline int ceil_log2(const T x) { return floor_log2(x) + ((x & -x) != x); } template constexpr inline int kth_bit(const T x, const unsigned int k) { return (x >> k) & 1; } template constexpr inline int parity(const T x) { return popcount(x) & 1; } // ! container template auto priqueue_comp(const Comparator comparator) { return std::priority_queue, Comparator>(comparator); } template void sort_unique_erase(Container& a) { std::sort(a.begin(), a.end()); a.erase(std::unique(a.begin(), a.end()), a.end()); } template auto foreach_adjacent_values(InputIterator first, InputIterator last, BiConsumer f) -> decltype(f(*first++, *last), void()) { if (first != last) for (auto itr = first, itl = itr++; itr != last; itl = itr++) f(*itl, *itr); } template auto foreach_adjacent_values(Container &&c, BiConsumer f) -> decltype(c.begin(), c.end(), void()) { foreach_adjacent_values(c.begin(), c.end(), f); } // ! other utilities // x <- min(x, y). returns true iff `x` has chenged. template inline bool chmin(T& x, const T& y) { return y >= x ? false : (x = y, true); } // x <- max(x, y). returns true iff `x` has chenged. template inline bool chmax(T& x, const T& y) { return y <= x ? false : (x = y, true); } template , std::nullptr_t> = nullptr> std::string bin(T val, int bit_num = -1) { std::string res; if (bit_num != -1) { for (int bit = bit_num; bit-- > 0;) res += '0' + ((val >> bit) & 1); } else { for (; val; val >>= 1) res += '0' + (val & 1); std::reverse(res.begin(), res.end()); } return res; } template , std::nullptr_t> = nullptr> std::vector digits_low_to_high(T val, T base = 10) { std::vector res; for (; val; val /= base) res.push_back(val % base); if (res.empty()) res.push_back(T{ 0 }); return res; } template , std::nullptr_t> = nullptr> std::vector digits_high_to_low(T val, T base = 10) { auto res = digits_low_to_high(val, base); std::reverse(res.begin(), res.end()); return res; } template std::string join(const std::vector& v, const std::string& sep, const std::string& end) { std::ostringstream ss; for (auto it = v.begin(); it != v.end();) { ss << *it; if (++it != v.end()) ss << sep; } ss << end; return ss.str(); } template auto transform_to_vector(const Func &f, const Seq &s) { std::vector> v; v.reserve(std::size(s)), std::transform(std::begin(s), std::end(s), std::back_inserter(v), f); return v; } template auto copy_to_vector(const Seq &s) { std::vector v; v.reserve(std::size(s)), std::copy(std::begin(s), std::end(s), std::back_inserter(v)); return v; } template Seq concat(Seq s, const Seq &t) { s.reserve(std::size(s) + std::size(t)); std::copy(std::begin(t), std::end(t), std::back_inserter(s)); return s; } template std::vector split(const Seq s, typename Seq::value_type delim) { std::vector res; for (auto itl = std::begin(s), itr = itl;; itl = ++itr) { while (itr != std::end(s) and *itr != delim) ++itr; res.emplace_back(itl, itr); if (itr == std::end(s)) return res; } } int digit_to_int(char c) { return c - '0'; } int lowercase_to_int(char c) { return c - 'a'; } int uppercase_to_int(char c) { return c - 'A'; } std::vector digit_str_to_ints(const std::string &s) { return transform_to_vector(digit_to_int, s); } std::vector lowercase_str_to_ints(const std::string &s) { return transform_to_vector(lowercase_to_int, s); } std::vector uppercase_str_to_ints(const std::string &s) { return transform_to_vector(uppercase_to_int, s); } template , std::enable_if_t< std::conjunction_v< std::is_invocable, std::is_invocable_r, std::invoke_result_t > >, std::nullptr_t> = nullptr > auto comparator(const ToKey &to_key, const CompareValue &compare_value = std::less<>()) { return [to_key, compare_value](const T& x, const T& y) { return compare_value(to_key(x), to_key(y)); }; } template , std::nullptr_t> = nullptr> std::vector sorted_indices(int n, const ToKey &to_key) { std::vector p(n); std::iota(p.begin(), p.end(), 0); std::sort(p.begin(), p.end(), comparator(to_key)); return p; } template , std::nullptr_t> = nullptr> std::vector sorted_indices(int n, const Compare &compare) { std::vector p(n); std::iota(p.begin(), p.end(), 0); std::sort(p.begin(), p.end(), compare); return p; } const std::string Yes = "Yes", No = "No", YES = "YES", NO = "NO"; namespace suisen {} using namespace suisen; using namespace std; struct io_setup { io_setup(int precision = 20) { std::ios::sync_with_stdio(false); std::cin.tie(nullptr); std::cout << std::fixed << std::setprecision(precision); } } io_setup_ {}; // ! code from here #define MULTIPLIED_TYPE __int128_t #include #include #include #include #include #include #ifndef COORDINATE_TYPE #define COORDINATE_TYPE long long #endif // COORDINATE_TYPE #ifndef MULTIPLIED_TYPE #define MULTIPLIED_TYPE long long #endif // MULTIPLIED_TYPE namespace suisen::integral_geometry { using coordinate_t = COORDINATE_TYPE; using multiplied_t = MULTIPLIED_TYPE; struct Point { coordinate_t x, y; constexpr Point(coordinate_t x = 0, coordinate_t y = 0) : x(x), y(y) {} template operator std::pair() const { return std::pair { T{ x }, U{ y } }; } template Point& operator=(const std::pair &p) { x = p.first, y = p.second; return *this; } friend Point operator+(const Point& p) { return p; } friend Point operator-(const Point& p) { return { -p.x, -p.y }; } friend Point operator+(const Point& lhs, const Point& rhs) { return { lhs.x + rhs.x, lhs.y + rhs.y }; } friend Point operator-(const Point& lhs, const Point& rhs) { return { lhs.x - rhs.x, lhs.y - rhs.y }; } friend Point operator*(const Point& lhs, const Point& rhs) { return { lhs.x * rhs.x - lhs.y * rhs.y, lhs.x * rhs.y + lhs.y * rhs.x }; } friend Point& operator+=(Point& lhs, const Point& rhs) { lhs.x += rhs.x, lhs.y += rhs.y; return lhs; } friend Point& operator-=(Point& lhs, const Point& rhs) { lhs.x -= rhs.x, lhs.y -= rhs.y; return lhs; } friend Point& operator*=(Point& lhs, const Point& rhs) { return lhs = lhs * rhs; } friend Point operator+(const Point& p, coordinate_t real) { return { p.x + real, p.y }; } friend Point operator-(const Point& p, coordinate_t real) { return { p.x - real, p.y }; } friend Point operator*(const Point& p, coordinate_t real) { return { p.x * real, p.y * real }; } friend Point operator/(const Point& p, coordinate_t real) { return { p.x / real, p.y / real }; } friend Point operator+=(Point& p, coordinate_t real) { p.x += real; return p; } friend Point operator-=(Point& p, coordinate_t real) { p.x -= real; return p; } friend Point operator*=(Point& p, coordinate_t real) { p.x *= real, p.y *= real; return p; } friend Point operator/=(Point& p, coordinate_t real) { p.x /= real, p.y /= real; return p; } friend Point operator+(coordinate_t real, const Point& p) { return { real + p.x, p.y }; } friend Point operator-(coordinate_t real, const Point& p) { return { real - p.x, -p.y }; } friend Point operator*(coordinate_t real, const Point& p) { return { real * p.x, real * p.y }; } friend bool operator==(const Point& lhs, const Point& rhs) { return lhs.x == rhs.x and lhs.y == rhs.y; } friend bool operator!=(const Point& lhs, const Point& rhs) { return not (lhs == rhs); } friend std::istream& operator>>(std::istream& in, Point& p) { return in >> p.x >> p.y; } friend std::ostream& operator<<(std::ostream& out, const Point& p) { return out << p.x << ' ' << p.y; } template coordinate_t get() const { if constexpr (I == 0) return x; else if constexpr (I == 1) return y; else assert(false); } template coordinate_t& get() { if constexpr (I == 0) return x; else if constexpr (I == 1) return y; else assert(false); } }; constexpr Point ZERO = { 0, 0 }; constexpr Point ONE = { 1, 0 }; constexpr Point I = { 0, 1 }; constexpr auto XY_COMPARATOR = [](const Point& p, const Point& q) { return p.x == q.x ? p.y < q.y : p.x < q.x; }; constexpr auto XY_COMPARATOR_GREATER = [](const Point& p, const Point& q) { return p.x == q.x ? p.y > q.y : p.x > q.x; }; constexpr auto YX_COMPARATOR = [](const Point& p, const Point& q) { return p.y == q.y ? p.x < q.x : p.y < q.y; }; constexpr auto YX_COMPARATOR_GREATER = [](const Point& p, const Point& q) { return p.y == q.y ? p.x > q.x : p.y > q.y; }; } // namespace suisen::integral_geometry namespace std { template <> struct tuple_size : integral_constant {}; template struct tuple_element { using type = suisen::integral_geometry::coordinate_t; }; } namespace suisen::integral_geometry { enum class Inclusion { OUT, ON, IN }; } namespace suisen::integral_geometry { // relations between three points X, Y, Z. struct ISP { static constexpr int L_CURVE = +1; // +---------------+ Z is in 'a' => ISP = +1 static constexpr int R_CURVE = -1; // |aaaaaaaaaaaaaaa| Z is in 'b' => ISP = -1 static constexpr int FRONT = +2; // |ddd X eee Y ccc| Z is in 'c' => ISP = +2 static constexpr int BACK = -2; // |bbbbbbbbbbbbbbb| Z is in 'd' => ISP = -2 static constexpr int MIDDLE = 0; // +---------------+ Z is in 'e' => ISP = 0 }; int sgn(coordinate_t x) { return x < 0 ? -1 : x > 0 ? +1 : 0; } int compare(coordinate_t x, coordinate_t y) { return sgn(x - y); } Point cartesian(const coordinate_t real, const coordinate_t imag) { return Point(real, imag); } Point conj(const Point& z) { return Point(z.x, -z.y); } double arg(const Point& z) { return std::atan2(z.y, z.x); } multiplied_t square_abs(const Point& z) { return multiplied_t(z.x) * z.x + multiplied_t(z.y) * z.y; } double abs(const Point& z) { return std::sqrt(square_abs(z)); } multiplied_t dot(const Point& a, const Point& b) { return multiplied_t(a.x) * b.x + multiplied_t(a.y) * b.y; } multiplied_t det(const Point& a, const Point& b) { return multiplied_t(a.x) * b.y - multiplied_t(a.y) * b.x; } // https://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=CGL_1_C int isp(const Point& a, const Point& b, const Point& c) { Point ab = b - a, ac = c - a; coordinate_t det_ab_ac = det(ab, ac); if (det_ab_ac > 0) return ISP::L_CURVE; if (det_ab_ac < 0) return ISP::R_CURVE; if (dot(ab, ac) < 0) return ISP::BACK; if (dot(a - b, c - b) < 0) return ISP::FRONT; return ISP::MIDDLE; } struct Line { Point a, b; Line() = default; Line(const Point& from, const Point& to) : a(from), b(to) {} }; struct Ray { Point a, b; Ray() = default; Ray(const Point& from, const Point& to) : a(from), b(to) {} }; struct Segment { Point a, b; Segment() = default; Segment(const Point& from, const Point& to) : a(from), b(to) {} }; struct Circle { Point center; coordinate_t radius; Circle() = default; Circle(const Point& c, const coordinate_t& r) : center(c), radius(r) {} }; // Triangle coordinate_t signed_area_doubled(const Point& a, const Point& b, const Point& c) { return det(b - a, c - a); } coordinate_t area_doubled(const Point& a, const Point& b, const Point& c) { return std::abs(signed_area_doubled(a, b, c)); } // Line // https://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=CGL_2_A template auto is_parallel(const line_t_1& l1, const line_t_2& l2) -> decltype(l1.a, l1.b, l2.a, l2.b, bool()) { return det(l1.b - l1.a, l2.b - l2.a) == 0; } // https://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=CGL_2_A template auto is_orthogonal(const line_t_1& l1, const line_t_2& l2) -> decltype(l1.a, l1.b, l2.a, l2.b, bool()) { return dot(l1.b - l1.a, l2.b - l2.a) == 0; } template auto on_the_same_line(const line_t_1& l1, const line_t_2& l2) -> decltype(l1.a, l1.b, l2.a, l2.b, bool()) { return is_parallel(l1, l2) and det(l1.b - l1.a, l2.a - l1.a) == 0; } Inclusion contains(const Line& l, const Point& p) { if (l.a.x == l.b.x) return p.x == l.a.x ? Inclusion::ON : Inclusion::OUT; coordinate_t a = p.x - l.a.x, b = p.y - l.a.y, c = l.b.x - p.x, d = l.b.y - p.y; return b * c == a * d ? Inclusion::ON : Inclusion::OUT; } Inclusion contains(const Ray& l, const Point& p) { if (contains(Line { l.a, l.b }, p) == Inclusion::OUT) return Inclusion::OUT; if (l.a.x == l.b.x) { if (l.a.y < l.b.y) return p.y >= l.a.y ? Inclusion::ON : Inclusion::OUT; else return p.y <= l.a.y ? Inclusion::ON : Inclusion::OUT; } else if (l.a.x < l.b.x) { return p.x >= l.a.x ? Inclusion::ON : Inclusion::OUT; } else { return p.x <= l.a.x ? Inclusion::ON : Inclusion::OUT; } } Inclusion contains(const Segment& l, const Point& p) { if (contains(Line { l.a, l.b }, p) == Inclusion::OUT) return Inclusion::OUT; if (l.a.x == l.b.x) { if (l.a.y < l.b.y) return p.y >= l.a.y and p.y <= l.b.y ? Inclusion::ON : Inclusion::OUT; else return p.y >= l.b.y and p.y <= l.a.y ? Inclusion::ON : Inclusion::OUT; } else if (l.a.x < l.b.x) { return p.x >= l.a.x and p.x <= l.b.x ? Inclusion::ON : Inclusion::OUT; } else { return p.x >= l.b.x and p.x <= l.a.x ? Inclusion::ON : Inclusion::OUT; } } bool operator==(const Line& l, const Line& m) { return on_the_same_line(l, m); } bool operator==(const Ray& l, const Ray& m) { return on_the_same_line(l, m) and l.a == m.a; } bool operator==(const Segment& l, const Segment& m) { return (l.a == m.a and l.b == m.b) or (l.a == m.b and l.b == m.a); } // "https://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=CGL_2_B" bool has_common_point(const Segment& l1, const Segment& l2) { int isp_1a = isp(l1.a, l1.b, l2.a), isp_1b = isp(l1.a, l1.b, l2.b); if (isp_1a * isp_1b > 0) return false; int isp_2a = isp(l2.a, l2.b, l1.a), isp_2b = isp(l2.a, l2.b, l1.b); if (isp_2a * isp_2b > 0) return false; return true; } // Polygon using Polygon = std::vector; // https://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=CGL_3_A coordinate_t signed_area_doubled(const Polygon& poly) { coordinate_t res = 0; int sz = poly.size(); for (int i = 0; i < sz; ++i) { int j = i + 1; if (j == sz) j = 0; res += signed_area_doubled(ZERO, poly[i], poly[j]); } return res; } // https://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=CGL_3_A coordinate_t area_doubled(const Polygon& poly) { return std::abs(signed_area_doubled(poly)); } // https://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=CGL_3_B template bool is_convex(const Polygon& poly) { int sz = poly.size(); for (int i = 0; i < sz; ++i) { int j = i + 1, k = i + 2; if (j >= sz) j -= sz; if (k >= sz) k -= sz; int dir = isp(poly[i], poly[j], poly[k]); if constexpr (accept_180_degree) { if (dir == ISP::R_CURVE) return false; } else { if (dir != ISP::L_CURVE) return false; } } return true; } // https://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=CGL_3_C Inclusion contains(const Polygon& poly, const Point& p) { bool in = false; int sz = poly.size(); for (int i = 0; i < sz; ++i) { int j = i + 1; if (j == sz) j -= sz; Point a = poly[i] - p, b = poly[j] - p; if (a.y > b.y) std::swap(a, b); if (a.y <= 0 and b.y > 0 and det(a, b) < 0) in = not in; if (det(a, b) == 0 and dot(a, b) <= 0) return Inclusion::ON; } return in ? Inclusion::IN : Inclusion::OUT; } std::pair convex_diameter(const Polygon& convex) { const int sz = convex.size(); if (sz <= 2) return { 0, sz - 1 }; auto [si, sj] = [&]{ auto [it_min, it_max] = std::minmax_element(convex.begin(), convex.end(), XY_COMPARATOR); return std::pair { it_min - convex.begin(), it_max - convex.begin() }; }(); coordinate_t max_dist = -1; std::pair argmax{ -1, -1 }; for (int i = si, j = sj; i != sj or j != si;) { if (multiplied_t dij = square_abs(convex[j] - convex[i]); dij > max_dist) max_dist = dij, argmax = { i, j }; int ni = (i + 1) % sz, nj = (j + 1) % sz; if (det(convex[ni] - convex[i], convex[nj] - convex[j]) < 0) i = ni; else j = nj; } return argmax; } // Circle // https://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=CGL_7_A int tangent_num(const Circle& c1, const Circle& c2) { coordinate_t r1 = c1.radius, r2 = c2.radius; if (r1 > r2) return tangent_num(c2, c1); coordinate_t d2 = square_abs(c1.center - c2.center); coordinate_t dp = d2 - (r1 + r2) * (r1 + r2); if (dp > 0) return 4; if (dp == 0) return 3; coordinate_t dn = d2 - (r2 - r1) * (r2 - r1); if (dn > 0) return 2; if (dn == 0) return 1; return 0; } bool has_common_point(const Circle& c1, const Circle& c2) { int tnum = tangent_num(c1, c2); return 1 <= tnum and tnum <= 3; } bool has_cross_point(const Circle& c1, const Circle& c2) { return tangent_num(c1, c2) == 2; } Inclusion contains(const Circle& c, const Point& p) { coordinate_t df = square_abs(c.center - p) - c.radius * c.radius; if (df > 0) return Inclusion::OUT; if (df < 0) return Inclusion::IN; return Inclusion::ON; } } // namespace suisen::integral_geometry using namespace integral_geometry; pair normalize(long long x, long long y) { long long g = gcd(x, y); x /= g, y /= g; if (x < 0) { x = -x; y = -y; } if (x == 0) { y = 1; } return { x, y }; } int main() { int n; read(n); vector points(n); read(points); vector ok(n, false); REP(i, n) { map, vector> mp; REP(j, n) if (i != j) { auto [x, y] = points[j] - points[i]; mp[normalize(x, y)].push_back(j); } for (auto [p, js] : mp) { js.push_back(i); if (js.size() <= 2) continue; if (js.size() >= 4) { for (int j : js) ok[j] = true; } else { sort(ALL(js), [&](int p, int q) { return XY_COMPARATOR(points[p] - points[i], points[q] - points[i]); }); ok[js.front()] = ok[js.back()] = true; } } } print(accumulate(ALL(ok), 0)); return 0; }