Tifa's CP Library

:warning: max_dis_cvh (src/code/geo2d/max_dis_cvh.hpp)

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Code

#ifndef TIFALIBS_GEO2D_MAX_DIS_CVH
#define TIFALIBS_GEO2D_MAX_DIS_CVH

#include "cvh.hpp"

namespace tifa_libs::geo {

// Max distance between two convex hulls
template <class FP>
constexpr FP max_dis_CVH(cvh<FP> const &ch1, cvh<FP> const &ch2) {
  u32 is = 0, js = 0;
  u32 szl = (u32)ch1.vs.size(), szr = (u32)ch2.vs.size();
  FP ans{};
  for (u32 i = 0; i < szl; ++i) is = ch1[i].y < ch1[is].y ? i : is;
  for (u32 i = 0; i < szr; ++i) js = ch2[i].y < ch2[js].y ? i : js;
  for (u32 i = 0; i < szl; ++i) {
    ans = std::max(ans, dist_PP(ch1[is], ch2[js]));
    int state;
    while ((state = sgn((ch1[is] - ch1[ch1.next(is)]) ^ (ch2[js] - ch2[ch2.next(js)]))) < 0) ans = std::max(ans, dist_PP(ch1[is], ch2[js = ch2.next(js)]));
    ans = std::max(ans, dist_PP(ch2[js], ch1[ch1.next(is = ch1.next(is))]));
    if (!state) {
      ans = std::max(ans, dist_PP(ch1[is], ch2[js]));
      js = ch2.next(js);
    }
  }
  return ans;
}

}  // namespace tifa_libs::geo

#endif
#line 1 "src/code/geo2d/max_dis_cvh.hpp"



#line 1 "src/code/geo2d/cvh.hpp"



#line 1 "src/code/geo2d/ins_ll.hpp"



#line 1 "src/code/geo2d/line.hpp"



#line 1 "src/code/geo2d/cross.hpp"



#line 1 "src/code/geo2d/point.hpp"



#line 1 "src/code/util/fp_comp.hpp"



#line 1 "src/code/util/fp_const.hpp"



#line 1 "src/code/util/util.hpp"



#include <bits/stdc++.h>

template <class T>
constexpr T abs(T x) { return x < 0 ? -x : x; }

using i8 = int8_t;
using i16 = int16_t;
using i32 = int32_t;
using i64 = int64_t;
using i128 = __int128_t;
using isz = ptrdiff_t;

using u8 = uint8_t;
using u16 = uint16_t;
using u32 = uint32_t;
using u64 = uint64_t;
using u128 = __uint128_t;
using usz = size_t;

using f32 = float;
using f64 = double;
using f128 = long double;

template <class T>
using ptt = std::pair<T, T>;
template <class T>
using pt3 = std::tuple<T, T, T>;
template <class T>
using pt4 = std::tuple<T, T, T, T>;

template <class T, usz N>
using arr = std::array<T, N>;
template <class T>
using vec = std::vector<T>;
template <class T>
using vvec = vec<vec<T>>;
template <class T>
using v3ec = vec<vvec<T>>;
template <class U, class T>
using vecp = vec<std::pair<U, T>>;
template <class U, class T>
using vvecp = vvec<std::pair<U, T>>;
template <class T>
using vecpt = vec<ptt<T>>;
template <class T>
using vvecpt = vvec<ptt<T>>;

template <class T, class C = std::less<T>>
using pq = std::priority_queue<T, vec<T>, C>;
template <class T>
using pqg = std::priority_queue<T, vec<T>, std::greater<T>>;

using strn = std::string;
using strnv = std::string_view;

using vecu = vec<u32>;
using vvecu = vvec<u32>;
using v3ecu = v3ec<u32>;
using vecu64 = vec<u64>;
using vecb = vec<bool>;
using vvecb = vvec<bool>;

#ifdef ONLINE_JUDGE
#undef assert
#define assert(x) 42
#endif

using namespace std::literals;

constexpr i8 operator""_i8(unsigned long long x) { return (i8)x; }
constexpr i16 operator""_i16(unsigned long long x) { return (i16)x; }
constexpr i32 operator""_i32(unsigned long long x) { return (i32)x; }
constexpr i64 operator""_i64(unsigned long long x) { return (i64)x; }
constexpr isz operator""_iz(unsigned long long x) { return (isz)x; }

constexpr u8 operator""_u8(unsigned long long x) { return (u8)x; }
constexpr u16 operator""_u16(unsigned long long x) { return (u16)x; }
constexpr u32 operator""_u32(unsigned long long x) { return (u32)x; }
constexpr u64 operator""_u64(unsigned long long x) { return (u64)x; }
constexpr usz operator""_uz(unsigned long long x) { return (usz)x; }

inline const auto fn_0 = [](auto&&...) {};


#line 5 "src/code/util/fp_const.hpp"

namespace tifa_libs {

using namespace std::numbers;

// std::sqrt(std::numeric_limits<FP>::epsilon())
template <std::floating_point FP>
constexpr inline FP eps_v = FP(1e-8L);

}  // namespace tifa_libs


#line 1 "src/code/util/traits.hpp"



#line 5 "src/code/util/traits.hpp"

namespace tifa_libs {

template <class T>
concept iterable_c = requires(T v) {
  { v.begin() } -> std::same_as<typename T::iterator>;
  { v.end() } -> std::same_as<typename T::iterator>;
};

template <class T>
concept container_c = iterable_c<T> && !std::derived_from<T, std::basic_string<typename T::value_type>>;

template <class T>
constexpr bool is_char_v = std::is_same_v<T, char> || std::is_same_v<T, signed char> || std::is_same_v<T, unsigned char>;
template <class T>
concept char_c = is_char_v<T>;

template <class T>
constexpr bool is_s128_v = std::is_same_v<T, __int128_t> || std::is_same_v<T, __int128>;
template <class T>
concept s128_c = is_s128_v<T>;

template <class T>
constexpr bool is_u128_v = std::is_same_v<T, __uint128_t> || std::is_same_v<T, unsigned __int128>;
template <class T>
concept u128_c = is_u128_v<T>;

template <class T>
constexpr bool is_i128_v = is_s128_v<T> || is_u128_v<T>;
template <class T>
concept i128_c = is_u128_v<T>;

template <class T>
constexpr bool is_int_v = std::is_integral_v<T> || is_i128_v<T>;
template <class T>
concept int_c = is_int_v<T>;

template <class T>
constexpr bool is_sint_v = is_s128_v<T> || (is_int_v<T> && std::is_signed_v<T>);
template <class T>
concept sint_c = is_sint_v<T>;

template <class T>
constexpr bool is_uint_v = is_u128_v<T> || (is_int_v<T> && std::is_unsigned_v<T>);
template <class T>
concept uint_c = is_uint_v<T>;

template <class T>
concept mint_c = requires(T x) {
  { x.mod() } -> uint_c;
  { x.val() } -> uint_c;
};

template <class T>
constexpr bool is_arithm_v = std::is_arithmetic_v<T> || is_int_v<T>;
template <class T>
concept arithm_c = is_arithm_v<T>;

template <class T>
struct to_sint : std::make_signed<T> {};
template <>
struct to_sint<u128> {
  using type = u128;
};
template <>
struct to_sint<i128> {
  using type = u128;
};
template <class T>
using to_sint_t = typename to_sint<T>::type;

template <class T>
struct to_uint : std::make_unsigned<T> {};
template <>
struct to_uint<u128> {
  using type = u128;
};
template <>
struct to_uint<i128> {
  using type = u128;
};
template <class T>
using to_uint_t = typename to_uint<T>::type;

}  // namespace tifa_libs


#line 6 "src/code/util/fp_comp.hpp"

namespace tifa_libs {

template <sint_c T>
constexpr int sgn(T x) { return (!!x) | (x >> (sizeof(T) * 8 - 1)); }
template <uint_c T>
constexpr int sgn(T x) { return !!x; }
template <std::floating_point FP>
constexpr int sgn(FP x) { return (x > eps_v<FP>)-(x < -eps_v<FP>); }

template <class FP>
constexpr bool is_neg(FP x) { return sgn(x) < 0; }
template <class FP>
constexpr bool is_zero(FP x) { return !sgn(x); }
template <class FP>
constexpr bool is_pos(FP x) { return sgn(x) > 0; }

template <int_c T>
constexpr int comp(T l, T r) { return sgn(l - r); }
template <std::floating_point FP>
constexpr int comp(FP l, FP r) { return sgn((l - r) / std::max({std::abs(l), std::abs(r), FP(1)})); }

template <class FP>
constexpr bool is_lt(FP l, FP r) { return comp(l, r) < 0; }
template <class FP>
constexpr bool is_eq(FP l, FP r) { return !comp(l, r); }
template <class FP>
constexpr bool is_gt(FP l, FP r) { return comp(l, r) > 0; }

}  // namespace tifa_libs


#line 5 "src/code/geo2d/point.hpp"

namespace tifa_libs::geo {

template <class FP>
struct point {
  FP x, y;
  explicit constexpr point(FP x = FP{}, FP y = FP{}) : x(x), y(y) {}

  friend std::istream &operator>>(std::istream &is, point &p) { return is >> p.x >> p.y; }
  friend std::ostream &operator<<(std::ostream &os, point const &p) { return os << p.x << ' ' << p.y; }

  // s * r + t * (1 - r)
  friend constexpr point lerp(point const &s, point const &t, FP r) { return s * r + t * (1 - r); }
  friend constexpr point mid_point(point const &s, point const &t) { return lerp(s, t, .5); }

  constexpr point &operator+=(FP n) {
    this->x += n;
    this->y += n;
    return *this;
  }
  constexpr point &operator-=(FP n) {
    this->x -= n;
    this->y -= n;
    return *this;
  }
  constexpr point &operator*=(FP n) {
    this->x *= n;
    this->y *= n;
    return *this;
  }
  constexpr point &operator/=(FP n) {
    this->x /= n;
    this->y /= n;
    return *this;
  }
  friend constexpr point operator+(point x, FP n) { return x += n; }
  friend constexpr point operator+(FP n, point x) { return x += n; }
  friend constexpr point operator-(point x, FP n) { return x -= n; }
  friend constexpr point operator-(FP n, point x) { return x -= n; }
  friend constexpr point operator*(point x, FP n) { return x *= n; }
  friend constexpr point operator*(FP n, point x) { return x *= n; }
  friend constexpr point operator/(point x, FP n) { return x /= n; }
  friend constexpr point operator/(FP n, point x) { return x /= n; }

  constexpr point &operator+=(point const &p) {
    this->x += p.x;
    this->y += p.y;
    return *this;
  }
  constexpr point &operator-=(point const &p) {
    this->x -= p.x;
    this->y -= p.y;
    return *this;
  }
  constexpr point operator+(point const &p) const { return point(*this) += p; }
  constexpr point operator-(point const &p) const { return point(*this) -= p; }

  constexpr point operator-() const { return point{-x, -y}; }
  constexpr auto operator<=>(point const &p) const {
    if (auto c = comp(x, p.x); c) return c;
    return comp(y, p.y);
  }
  constexpr bool operator==(point const &p) const { return is_eq(x, p.x) && is_eq(y, p.y); }

  constexpr FP operator*(point const &p) const { return x * p.x + y * p.y; }
  constexpr FP operator^(point const &p) const { return x * p.y - y * p.x; }

  constexpr auto arg() const { return std::atan2(y, x); }
  constexpr FP norm2() const { return x * x + y * y; }
  constexpr FP norm() const { return std::hypot(x, y); }
  constexpr point &do_unit() { return *this /= norm(); }

  static constexpr u32 QUAD__[9] = {6, 7, 8, 5, 0, 1, 4, 3, 2};
  // 4 3 2
  // 5 0 1
  // 6 7 8
  constexpr u32 quad() const { return QUAD__[(sgn(y) + 1) * 3 + sgn(x) + 1]; }

  constexpr point &do_rot(FP theta) {
    FP x0 = x, y0 = y, ct = std::cos(theta), st = std::sin(theta);
    x = x0 * ct - y0 * st;
    y = x0 * st + y0 * ct;
    return *this;
  }
  constexpr point &do_rot90() {
    FP tmp = x;
    x = -y;
    y = tmp;
    return *this;
  }
  friend constexpr point rot90(point p) { return p.do_rot90(); }
  constexpr point &do_rot270() {
    FP tmp = y;
    y = -x;
    x = tmp;
    return *this;
  }
  friend constexpr point rot270(point p) { return p.do_rot270(); }
};

}  // namespace tifa_libs::geo


#line 5 "src/code/geo2d/cross.hpp"

namespace tifa_libs::geo {

// (a - o) ^ (b - o)
template <class FP>
constexpr FP cross(point<FP> const &o, point<FP> const &a, point<FP> const &b) { return (a.x - o.x) * (b.y - o.y) - (b.x - o.x) * (a.y - o.y); }
template <class FP>
constexpr FP cross_unit(point<FP> const &o, point<FP> const &a, point<FP> const &b) { return (a - o).do_unit() ^ (b - o).do_unit(); }
template <class FP>
constexpr int sgn_cross(point<FP> const &o, point<FP> const &a, point<FP> const &b) { return sgn(cross_unit(o, a, b)); }

}  // namespace tifa_libs::geo


#line 5 "src/code/geo2d/line.hpp"

namespace tifa_libs::geo {

template <class FP>
struct line {
  point<FP> l, r;
  constexpr line() {}
  constexpr line(point<FP> const &s, point<FP> const &t) : l(s), r(t) {}
  constexpr line(point<FP> const &s, FP angle_x) : l(s), r(s + is_eq(angle_x, pi_v<FP> / 2) ? point<FP>{0, 1} : point<FP>{1, std::tan(angle_x)}) { assert(angle_x > 0 && angle_x < pi_v<FP>); }
  // ax + by + c = 0
  constexpr line(FP a, FP b, FP c) {
    if (is_zero(a)) l = {0, -c / b}, r = {1, -c / b};
    else if (is_zero(b)) l = {-c / a, 0}, r = {-c / a, 1};
    else l = {0, -c / b}, r = {1, -(c + a) / b};
  }
  constexpr line(FP s_x, FP s_y, FP t_x, FP t_y) : l(s_x, s_y), r(t_x, t_y) {}

  friend std::istream &operator>>(std::istream &is, line &l) { return is >> l.l >> l.r; }
  friend std::ostream &operator<<(std::ostream &os, line const &l) { return os << l.l << ' ' << l.r; }

  constexpr point<FP> direction() const { return r - l; }
  constexpr bool is_parallel(line const &r) const { return is_zero(direction() ^ r.direction()); }
  friend constexpr bool is_parallel(line const &l, line const &r) { return l.is_parallel(r); }
  constexpr bool is_same_dir(line const &r) const { return is_parallel(r) && is_pos(direction() * r.direction()); }
  friend constexpr bool is_same_dir(line const &l, line const &r) { return l.is_same_dir(r); }

  friend constexpr bool operator==(line const &l, line const &r) { return l.l == r.l && l.r == r.r; }
  friend constexpr auto operator<=>(line const &l, line const &r) {
    if (l == r) return 0;
    if (l.is_same_dir(r)) return r.is_include_strict(l.l) ? -1 : 1;
    auto vl = l.direction(), vr = r.direction();
    if (vl.quad() != vr.quad()) return (i32)vl.quad() - (i32)vr.quad();
    return -sgn(vl ^ vr);
  }

  // half plane
  constexpr bool is_include_strict(point<FP> const &p) const { return is_pos(cross(l, r, p)); }
  // half plane
  constexpr bool is_include(point<FP> const &p) const { return !is_neg(cross(l, r, p)); }

  // translate @dist along the direction of half plane
  constexpr line &do_push(FP dist) {
    point delta = direction().do_rot90().do_unit() * dist;
    l += delta;
    r += delta;
    return *this;
  }
};

}  // namespace tifa_libs::geo


#line 5 "src/code/geo2d/ins_ll.hpp"

namespace tifa_libs::geo {

// judge if two lines are intersected or not
template <class FP>
constexpr bool is_ins_LL(line<FP> const &l1, line<FP> const &l2) { return !is_zero(cross(l2.l, l2.r, l1.l) - cross(l2.l, l2.r, l1.r)); }
// intersection point of two lines
template <class FP>
constexpr point<FP> ins_LL(line<FP> const &l1, line<FP> const &l2) {
  FP a1 = cross(l2.l, l2.r, l1.l), a2 = -cross(l2.l, l2.r, l1.r);
  return (l1.l * a2 + l1.r * a1) / (a1 + a2);
}
template <class FP>
constexpr point<FP> ins_LL(line<FP> const &l, FP a, FP b, FP c) {
  FP a1 = abs(a * l.l.x + b * l.l.y + c), a2 = abs(a * l.r.x + b * l.r.y + c);
  return (l.l * a2 + l.r * a1) / (a1 + a2);
}

}  // namespace tifa_libs::geo


#line 1 "src/code/geo2d/polygon.hpp"



#line 1 "src/code/edh/discretization.hpp"



#line 5 "src/code/edh/discretization.hpp"

namespace tifa_libs {

template <iterable_c T = vec<int>>
constexpr T uniq(T v) {
  std::ranges::sort(v);
  auto [f, l] = std::ranges::unique(v);
  v.erase(f, l);
  return v;
}
template <iterable_c T = vec<int>>
constexpr std::pair<T, vec<u32>> gen_id(T const &v) {
  T _ = uniq(v);
  vec<u32> _1;

  for (u32 i = 0; i < v.size(); ++i) _1.push_back(u32(std::ranges::lower_bound(_, v[i]) - _.begin()));
  return {_, _1};
}

}  // namespace tifa_libs


#line 1 "src/code/geo2d/dist_pp.hpp"



#line 5 "src/code/geo2d/dist_pp.hpp"

namespace tifa_libs::geo {

// distance of two points (Euclidian)
template <class FP>
constexpr FP dist_PP(point<FP> const &p1, point<FP> const &p2) { return (p1 - p2).norm(); }

}  // namespace tifa_libs::geo


#line 7 "src/code/geo2d/polygon.hpp"

namespace tifa_libs::geo {

template <class FP>
struct polygon {
  vec<point<FP>> vs;

  constexpr polygon() {}
  explicit constexpr polygon(u32 sz) : vs(sz) {}
  explicit constexpr polygon(vec<point<FP>> const &vs_) : vs(vs_) {}

  friend std::istream &operator>>(std::istream &is, polygon &p) {
    for (auto &i : p.vs) is >> i;
    return is;
  }
  friend std::ostream &operator<<(std::ostream &os, polygon const &p) {
    if (p.vs.empty()) return os;
    for (auto it = p.vs.begin(); it != p.vs.end() - 1; ++it) os << *it << ' ';
    return os << p.vs.back();
  }
  constexpr point<FP> &operator[](u32 x) { return vs[x]; }
  constexpr point<FP> const &operator[](u32 x) const { return vs[x]; }

  constexpr polygon &resort() {
    std::ranges::sort(vs);
    return *this;
  }
  constexpr polygon &reunique() {
    vs = uniq(vs);
    return *this;
  }

  constexpr auto prev(typename vec<point<FP>>::const_iterator it) const { return --(it == vs.begin() ? it = vs.end() : it); }
  constexpr auto next(typename vec<point<FP>>::const_iterator it) const { return ++it == vs.end() ? vs.begin() : it; }
  constexpr u32 prev(u32 idx) const { return idx == 0 ? (u32)vs.size() - 1 : idx - 1; }
  constexpr u32 next(u32 idx) const { return idx + 1 == (u32)vs.size() ? 0 : idx + 1; }

  constexpr FP circum() const {
    FP ret = dist_PP(vs.back(), vs.front());
    for (u32 i = 0; i < (u32)vs.size() - 1; ++i) ret += dist_PP(vs[i], vs[i + 1]);
    return ret;
  }
  constexpr FP area() const {
    if (vs.size() < 3) return 0;
    FP ret = vs.back() ^ vs.front();
    for (u32 i = 0; i < (u32)vs.size() - 1; ++i) ret += vs[i] ^ vs[i + 1];
    return ret / 2;
  }
  constexpr bool is_convex() const {
    bool flag[2] = {false, false};
    u32 n = (u32)vs.size();
    if (n < 3) return true;
    for (u32 i = 0, j = next(i), k = next(j); i < n; ++i, j = next(j), k = next(k)) {
      auto sgn = sgn_cross(vs[i], vs[j], vs[k]);
      if (sgn) flag[(sgn + 1) / 2] = true;
      if (flag[0] && flag[1]) return false;
    }
    return true;
  }
};

}  // namespace tifa_libs::geo


#line 6 "src/code/geo2d/cvh.hpp"

namespace tifa_libs::geo {

template <class FP>
struct cvh : public polygon<FP> {
  constexpr cvh() {}
  explicit constexpr cvh(u32 sz) : polygon<FP>(sz) {}
  explicit constexpr cvh(vec<point<FP>> const &vs_, bool inited = false, bool strict = true) : polygon<FP>(vs_) {
    if (!inited) strict ? init() : init_nonstrict();
  }

  friend std::istream &operator>>(std::istream &is, cvh &ch) {
    for (auto &i : ch.vs) is >> i;
    return is;
  }
  friend std::ostream &operator<<(std::ostream &os, cvh<FP> const &ch) {
    if (ch.vs.empty()) return os;
    for (auto it = ch.vs.begin(); it != ch.vs.end() - 1; ++it) os << *it << ' ';
    return os << ch.vs.back();
  }

  constexpr cvh &init() {
    u32 n = (u32)this->vs.size();
    if (n <= 1) return *this;
    this->resort();
    vec<point<FP>> cvh(n * 2);
    u32 sz_cvh = 0;
    for (u32 i = 0; i < n; cvh[sz_cvh++] = this->vs[i++])
      while (sz_cvh > 1 && sgn_cross(cvh[sz_cvh - 2], cvh[sz_cvh - 1], this->vs[i]) <= 0) --sz_cvh;
    for (u32 i = n - 2, t = sz_cvh; ~i; cvh[sz_cvh++] = this->vs[i--])
      while (sz_cvh > t && sgn_cross(cvh[sz_cvh - 2], cvh[sz_cvh - 1], this->vs[i]) <= 0) --sz_cvh;
    cvh.resize(sz_cvh - 1);
    this->vs = cvh;
    return *this;
  }
  constexpr cvh &init_nonstrict() {
    this->reunique();
    u32 n = (u32)this->vs.size();
    if (n <= 1) return *this;
    vec<point<FP>> cvh(n * 2);
    u32 sz_cvh = 0;
    for (u32 i = 0; i < n; cvh[sz_cvh++] = this->vs[i++])
      while (sz_cvh > 1 && sgn_cross(cvh[sz_cvh - 2], cvh[sz_cvh - 1], this->vs[i]) < 0) --sz_cvh;
    for (u32 i = n - 2, t = sz_cvh; ~i; cvh[sz_cvh++] = this->vs[i--])
      while (sz_cvh > t && sgn_cross(cvh[sz_cvh - 2], cvh[sz_cvh - 1], this->vs[i]) < 0) --sz_cvh;
    cvh.resize(sz_cvh - 1);
    this->vs = cvh;
    return *this;
  }

  constexpr FP diameter() const {
    u32 n = (u32)this->vs.size();
    if (n <= 1) return FP{};
    u32 is = 0, js = 0;
    for (u32 k = 1; k < n; ++k) {
      is = this->vs[k] < this->vs[is] ? k : is;
      js = this->vs[js] < this->vs[k] ? k : js;
    }
    u32 i = is, j = js;
    FP ret = dist_PP(this->vs[i], this->vs[j]);
    do {
      (++(((this->vs[this->next(i)] - this->vs[i]) ^ (this->vs[this->next(j)] - this->vs[j])) >= 0 ? j : i)) %= n;
      ret = std::max(ret, dist_PP(this->vs[i], this->vs[j]));
    } while (i != is || j != js);
    return ret;
  }

  constexpr cvh &do_minkowski_sum_nonstrict(cvh<FP> const &r) {
    u32 n = (u32)this->vs.size(), m = (u32)r.vs.size();
    if (!m) return *this;
    if (!n) return *this = r;
    vec<point<FP>> result;
    result.reserve(n + m);
    u32 midxl = 0;
    for (u32 i = 1; i < n; ++i) midxl = this->vs[i] < this->vs[midxl] ? i : midxl;
    u32 midxr = 0;
    for (u32 i = 1; i < m; ++i) midxr = r[i] < r[midxr] ? i : midxr;
    bool fl = false, fr = false;
    for (u32 idxl = midxl, idxr = midxr; !(idxl == midxl && fl) || !(idxr == midxr && fr);) {
      point diffl = this->vs[this->next(idxl)] - this->vs[idxl], diffr = r[r.next(idxr)] - r[idxr];
      bool f = !(idxl == midxl && fl) && ((idxr == midxr && fr) || is_pos(diffl ^ diffr));
      result.push_back(this->vs[idxl] + r[idxr] + (f ? diffl : diffr));
      (f ? idxl : idxr) = (f ? this->next(idxl) : r.next(idxr));
      (f ? fl : fr) |= !(f ? idxl : idxr);
    }
    this->vs = result;
    return *this;
  }

  constexpr cvh &do_minkowski_sum(cvh<FP> const &r) { return do_minkowski_sum_nonstrict(r).init(); }

  constexpr cvh &do_ins_CVHhP(line<FP> const &l) {
    u32 n = (u32)this->vs.size();
    vec<point<FP>> cvc;
    for (u32 i = 0; i < n; ++i) {
      point p1 = this->vs[i], p2 = this->vs[this->next(i)];
      int d1 = sgn_cross(l.l, l.r, p1), d2 = sgn_cross(l.l, l.r, p2);
      if (d1 >= 0) cvc.push_back(p1);
      if (d1 * d2 < 0) cvc.push_back(ins_LL({p1, p2}, l));
    }
    this->vs = cvc;
    return *this;
  }
};

}  // namespace tifa_libs::geo


#line 5 "src/code/geo2d/max_dis_cvh.hpp"

namespace tifa_libs::geo {

// Max distance between two convex hulls
template <class FP>
constexpr FP max_dis_CVH(cvh<FP> const &ch1, cvh<FP> const &ch2) {
  u32 is = 0, js = 0;
  u32 szl = (u32)ch1.vs.size(), szr = (u32)ch2.vs.size();
  FP ans{};
  for (u32 i = 0; i < szl; ++i) is = ch1[i].y < ch1[is].y ? i : is;
  for (u32 i = 0; i < szr; ++i) js = ch2[i].y < ch2[js].y ? i : js;
  for (u32 i = 0; i < szl; ++i) {
    ans = std::max(ans, dist_PP(ch1[is], ch2[js]));
    int state;
    while ((state = sgn((ch1[is] - ch1[ch1.next(is)]) ^ (ch2[js] - ch2[ch2.next(js)]))) < 0) ans = std::max(ans, dist_PP(ch1[is], ch2[js = ch2.next(js)]));
    ans = std::max(ans, dist_PP(ch2[js], ch1[ch1.next(is = ch1.next(is))]));
    if (!state) {
      ans = std::max(ans, dist_PP(ch1[is], ch2[js]));
      js = ch2.next(js);
    }
  }
  return ans;
}

}  // namespace tifa_libs::geo


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