CP-Algorithms Library

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:heavy_check_mark: cp-algo/geometry/closest_pair.hpp

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#ifndef CP_ALGO_GEOMETRY_CLOSEST_PAIR_HPP
#define CP_ALGO_GEOMETRY_CLOSEST_PAIR_HPP
#include "../random/rng.hpp"
#include "../util/big_alloc.hpp"
#include "point.hpp"
#include <vector>
#include <map>
namespace cp_algo::geometry {
    // Rabin & Lipton
    auto closest_pair(auto const& r) {
        using point = std::decay_t<decltype(r[0])>;
        size_t n = size(r);
        int64_t md = 1e18;
        for(size_t i = 0; i < n / 100; i++) {
            auto A = random::rng() % n;
            auto B = random::rng() % n;
            if(A != B) {
                md = std::min(md, norm(r[A] - r[B]));
                if(md == 0) {
                    return std::pair{A, B};
                }
            }
        }
        big_map<point, big_vector<size_t>> neigs;
        md = (int64_t)ceil(sqrt((double)md));
        for(size_t i = 0; i < n; i++) {
            neigs[r[i] / md].push_back(i);
        }
        size_t a = 0, b = 1;
        md = norm(r[a] - r[b]);
        for(auto &[p, id]: neigs) {
            for(int dx: {-1, 0, 1}) {
                for(int dy: {-1, 0, 1}) {
                    auto pp = p + point{dx, dy};
                    if(!neigs.count(pp)) {
                        continue;
                    }
                    for(size_t i: neigs[pp]) {
                        for(size_t j: id) {
                            if(j == i) {
                                break;
                            }
                            int64_t cur = norm(r[i] - r[j]);
                            if(cur < md) {
                                md = cur;
                                a = i;
                                b = j;
                            }
                        }
                    }
                }
            }
        }
        return std::pair{a, b};
    }
}
#endif // CP_ALGO_GEOMETRY_CLOSEST_PAIR_HPP
#line 1 "cp-algo/geometry/closest_pair.hpp"


#line 1 "cp-algo/random/rng.hpp"


#include <chrono>
#include <random>
namespace cp_algo::random {
    std::mt19937_64 gen(
        std::chrono::steady_clock::now().time_since_epoch().count()
    );
    uint64_t rng() {
        return gen();
    }
}

#line 1 "cp-algo/util/big_alloc.hpp"



#include <set>
#include <map>
#include <deque>
#include <stack>
#include <queue>
#include <vector>
#include <string>
#include <cstddef>
#include <iostream>
#include <generator>
#include <forward_list>

// Single macro to detect POSIX platforms (Linux, Unix, macOS)
#if defined(__linux__) || defined(__unix__) || (defined(__APPLE__) && defined(__MACH__))
#  define CP_ALGO_USE_MMAP 1
#  include <sys/mman.h>
#else
#  define CP_ALGO_USE_MMAP 0
#endif

namespace cp_algo {
    template <typename T, size_t Align = 32>
    class big_alloc {
        static_assert( Align >= alignof(void*), "Align must be at least pointer-size");
        static_assert(std::popcount(Align) == 1, "Align must be a power of two");
    public:
        using value_type = T;
        template <class U> struct rebind { using other = big_alloc<U, Align>; };
        constexpr bool operator==(const big_alloc&) const = default;
        constexpr bool operator!=(const big_alloc&) const = default;

        big_alloc() noexcept = default;
        template <typename U, std::size_t A>
        big_alloc(const big_alloc<U, A>&) noexcept {}

        [[nodiscard]] T* allocate(std::size_t n) {
            std::size_t padded = round_up(n * sizeof(T));
            std::size_t align = std::max<std::size_t>(alignof(T),  Align);
#if CP_ALGO_USE_MMAP
            if (padded >= MEGABYTE) {
                void* raw = mmap(nullptr, padded,
                                PROT_READ | PROT_WRITE,
                                MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
                madvise(raw, padded, MADV_HUGEPAGE);
                madvise(raw, padded, MADV_POPULATE_WRITE);
                return static_cast<T*>(raw);
            }
#endif
            return static_cast<T*>(::operator new(padded, std::align_val_t(align)));
        }

        void deallocate(T* p, std::size_t n) noexcept {
            if (!p) return;
            std::size_t padded = round_up(n * sizeof(T));
            std::size_t align  = std::max<std::size_t>(alignof(T),  Align);
    #if CP_ALGO_USE_MMAP
            if (padded >= MEGABYTE) { munmap(p, padded); return; }
    #endif
            ::operator delete(p, padded, std::align_val_t(align));
        }

    private:
        static constexpr std::size_t MEGABYTE = 1 << 20;
        static constexpr std::size_t round_up(std::size_t x) noexcept {
            return (x + Align - 1) / Align * Align;
        }
    };

    template<typename T> using big_vector = std::vector<T, big_alloc<T>>;
    template<typename T> using big_basic_string = std::basic_string<T, std::char_traits<T>, big_alloc<T>>;
    template<typename T> using big_deque = std::deque<T, big_alloc<T>>;
    template<typename T> using big_stack = std::stack<T, big_deque<T>>;
    template<typename T> using big_queue = std::queue<T, big_deque<T>>;
    template<typename T> using big_priority_queue = std::priority_queue<T, big_vector<T>>;
    template<typename T> using big_forward_list = std::forward_list<T, big_alloc<T>>;
    using big_string = big_basic_string<char>;

    template<typename Key, typename Value, typename Compare = std::less<Key>>
    using big_map = std::map<Key, Value, Compare, big_alloc<std::pair<const Key, Value>>>;
    template<typename T, typename Compare = std::less<T>>
    using big_multiset = std::multiset<T, Compare, big_alloc<T>>;
    template<typename T, typename Compare = std::less<T>>
    using big_set = std::set<T, Compare, big_alloc<T>>;
    template<typename Ref, typename V = void>

    using big_generator = std::generator<Ref, V, big_alloc<std::byte>>;
}

// Deduction guide to make elements_of with big_generator default to big_alloc
namespace std::ranges {
    template<typename Ref, typename V>
    elements_of(cp_algo::big_generator<Ref, V>&&) -> elements_of<cp_algo::big_generator<Ref, V>&&, cp_algo::big_alloc<std::byte>>;
}


#line 1 "cp-algo/geometry/point.hpp"


#line 1 "cp-algo/util/complex.hpp"


#line 4 "cp-algo/util/complex.hpp"
#include <cmath>
#include <type_traits>
#line 1 "cp-algo/util/simd.hpp"


#include <experimental/simd>
#include <cstdint>
#line 6 "cp-algo/util/simd.hpp"
#include <memory>

#if defined(__x86_64__) && !defined(CP_ALGO_DISABLE_AVX2)
#define CP_ALGO_SIMD_AVX2_TARGET _Pragma("GCC target(\"avx2\")")
#else
#define CP_ALGO_SIMD_AVX2_TARGET
#endif

#define CP_ALGO_SIMD_PRAGMA_PUSH \
    _Pragma("GCC push_options") \
    CP_ALGO_SIMD_AVX2_TARGET

CP_ALGO_SIMD_PRAGMA_PUSH
namespace cp_algo {
    template<typename T, size_t len>
    using simd [[gnu::vector_size(len * sizeof(T))]] = T;
    using u64x8 = simd<uint64_t, 8>;
    using u32x16 = simd<uint32_t, 16>;
    using i64x4 = simd<int64_t, 4>;
    using u64x4 = simd<uint64_t, 4>;
    using u32x8 = simd<uint32_t, 8>;
    using u16x16 = simd<uint16_t, 16>;
    using i32x4 = simd<int32_t, 4>;
    using u32x4 = simd<uint32_t, 4>;
    using u16x8 = simd<uint16_t, 8>;
    using u16x4 = simd<uint16_t, 4>;
    using i16x4 = simd<int16_t, 4>;
    using u8x32 = simd<uint8_t, 32>;
    using u8x8 = simd<uint8_t, 8>;
    using u8x4 = simd<uint8_t, 4>;
    using dx4 = simd<double, 4>;

    inline dx4 abs(dx4 a) {
        return dx4{
            std::abs(a[0]),
            std::abs(a[1]),
            std::abs(a[2]),
            std::abs(a[3])
        };
    }

    // https://stackoverflow.com/a/77376595
    // works for ints in (-2^51, 2^51)
    static constexpr dx4 magic = dx4() + (3ULL << 51);
    inline i64x4 lround(dx4 x) {
        return i64x4(x + magic) - i64x4(magic);
    }
    inline dx4 to_double(i64x4 x) {
        return dx4(x + i64x4(magic)) - magic;
    }

    inline dx4 round(dx4 a) {
        return dx4{
            std::nearbyint(a[0]),
            std::nearbyint(a[1]),
            std::nearbyint(a[2]),
            std::nearbyint(a[3])
        };
    }

    inline u64x4 low32(u64x4 x) {
        return x & uint32_t(-1);
    }
    inline auto swap_bytes(auto x) {
        return decltype(x)(__builtin_shufflevector(u32x8(x), u32x8(x), 1, 0, 3, 2, 5, 4, 7, 6));
    }
    inline u64x4 montgomery_reduce(u64x4 x, uint32_t mod, uint32_t imod) {
#ifdef __AVX2__
        auto x_ninv = u64x4(_mm256_mul_epu32(__m256i(x), __m256i() + imod));
        x += u64x4(_mm256_mul_epu32(__m256i(x_ninv), __m256i() + mod));
#else
        auto x_ninv = u64x4(u32x8(low32(x)) * imod);
        x += x_ninv * uint64_t(mod);
#endif
        return swap_bytes(x);
    }

    inline u64x4 montgomery_mul(u64x4 x, u64x4 y, uint32_t mod, uint32_t imod) {
#ifdef __AVX2__
        return montgomery_reduce(u64x4(_mm256_mul_epu32(__m256i(x), __m256i(y))), mod, imod);
#else
        return montgomery_reduce(x * y, mod, imod);
#endif
    }
    inline u32x8 montgomery_mul(u32x8 x, u32x8 y, uint32_t mod, uint32_t imod) {
        return u32x8(montgomery_mul(u64x4(x), u64x4(y), mod, imod)) |
               u32x8(swap_bytes(montgomery_mul(u64x4(swap_bytes(x)), u64x4(swap_bytes(y)), mod, imod)));
    }
    inline dx4 rotate_right(dx4 x) {
        static constexpr u64x4 shuffler = {3, 0, 1, 2};
        return __builtin_shuffle(x, shuffler);
    }

    template<std::size_t Align = 32>
    inline bool is_aligned(const auto* p) noexcept {
        return (reinterpret_cast<std::uintptr_t>(p) % Align) == 0;
    }

    template<class Target>
    inline Target& vector_cast(auto &&p) {
        return *reinterpret_cast<Target*>(std::assume_aligned<alignof(Target)>(&p));
    }
}
#pragma GCC pop_options

#line 7 "cp-algo/util/complex.hpp"
CP_ALGO_SIMD_PRAGMA_PUSH
namespace cp_algo {
    // Custom implementation, since std::complex is UB on non-floating types
    template<typename T>
    struct complex {
        using value_type = T;
        T x, y;
        inline constexpr complex(): x(), y() {}
        inline constexpr complex(T const& x): x(x), y() {}
        inline constexpr complex(T const& x, T const& y): x(x), y(y) {}
        inline complex& operator *= (T const& t) {x *= t; y *= t; return *this;}
        inline complex& operator /= (T const& t) {x /= t; y /= t; return *this;}
        inline complex operator * (T const& t) const {return complex(*this) *= t;}
        inline complex operator / (T const& t) const {return complex(*this) /= t;}
        inline complex& operator += (complex const& t) {x += t.x; y += t.y; return *this;}
        inline complex& operator -= (complex const& t) {x -= t.x; y -= t.y; return *this;}
        inline complex operator * (complex const& t) const {return {x * t.x - y * t.y, x * t.y + y * t.x};}
        inline complex operator / (complex const& t) const {return *this * t.conj() / t.norm();}
        inline complex operator + (complex const& t) const {return complex(*this) += t;}
        inline complex operator - (complex const& t) const {return complex(*this) -= t;}
        inline complex& operator *= (complex const& t) {return *this = *this * t;}
        inline complex& operator /= (complex const& t) {return *this = *this / t;}
        inline complex operator - () const {return {-x, -y};}
        inline complex conj() const {return {x, -y};}
        inline T norm() const {return x * x + y * y;}
        inline T abs() const {return std::sqrt(norm());}
        inline T const real() const {return x;}
        inline T const imag() const {return y;}
        inline T& real() {return x;}
        inline T& imag() {return y;}
        inline static constexpr complex polar(T r, T theta) {return {T(r * cos(theta)), T(r * sin(theta))};}
        inline auto operator <=> (complex const& t) const = default;
    };
    template<typename T> inline complex<T> conj(complex<T> const& x) {return x.conj();}
    template<typename T> inline T norm(complex<T> const& x) {return x.norm();}
    template<typename T> inline T abs(complex<T> const& x) {return x.abs();}
    template<typename T> inline T& real(complex<T> &x) {return x.real();}
    template<typename T> inline T& imag(complex<T> &x) {return x.imag();}
    template<typename T> inline T const real(complex<T> const& x) {return x.real();}
    template<typename T> inline T const imag(complex<T> const& x) {return x.imag();}
    template<typename T>
    inline constexpr complex<T> polar(T r, T theta) {
        return complex<T>::polar(r, theta);
    }
    template<typename T>
    inline std::ostream& operator << (std::ostream &out, complex<T> const& x) {
        return out << x.real() << ' ' << x.imag();
    }
}
#pragma GCC pop_options

#line 5 "cp-algo/geometry/point.hpp"
namespace cp_algo::geometry {
    template<typename ftype>
    struct point_t: complex<ftype> {
        using Base = complex<ftype>;
        using Base::Base;

        point_t(Base const& t): Base(t) {}
        
        auto operator <=> (point_t const& t) const {
            return std::pair{y(), -x()} <=> std::pair{t.y(), -t.x()};
        }

        ftype x() const {return Base::real();}
        ftype y() const {return Base::imag();}

        point_t cmul(point_t const& t) const {return conj(*this) * t;}
        ftype dot(point_t const& t) const {return cmul(t).x();}
        ftype cross(point_t const& t) const {return cmul(t).y();}

        static constexpr point_t O = {0, 0};

        int half() const {
            return *this < O ? -1 : *this == O ? 0 : 1;
        }

        static bool ccw(point_t const& a, point_t const& b) {
            return a.cross(b) > 0;
        }
        static bool ccw_abs(point_t const& a, point_t const & b) {
            return std::tuple{a.half(), (ftype)0, norm(a)} <
                   std::tuple{b.half(), a.cross(b), norm(b)};
        }
        void read() {
            ftype _x, _y;
            std::cin >> _x >> _y;
            *this = {_x, _y};
        }
        void print() const {
            std::cout << x() << ' ' << y() << "\n";
        }
    };
}

#line 8 "cp-algo/geometry/closest_pair.hpp"
namespace cp_algo::geometry {
    // Rabin & Lipton
    auto closest_pair(auto const& r) {
        using point = std::decay_t<decltype(r[0])>;
        size_t n = size(r);
        int64_t md = 1e18;
        for(size_t i = 0; i < n / 100; i++) {
            auto A = random::rng() % n;
            auto B = random::rng() % n;
            if(A != B) {
                md = std::min(md, norm(r[A] - r[B]));
                if(md == 0) {
                    return std::pair{A, B};
                }
            }
        }
        big_map<point, big_vector<size_t>> neigs;
        md = (int64_t)ceil(sqrt((double)md));
        for(size_t i = 0; i < n; i++) {
            neigs[r[i] / md].push_back(i);
        }
        size_t a = 0, b = 1;
        md = norm(r[a] - r[b]);
        for(auto &[p, id]: neigs) {
            for(int dx: {-1, 0, 1}) {
                for(int dy: {-1, 0, 1}) {
                    auto pp = p + point{dx, dy};
                    if(!neigs.count(pp)) {
                        continue;
                    }
                    for(size_t i: neigs[pp]) {
                        for(size_t j: id) {
                            if(j == i) {
                                break;
                            }
                            int64_t cur = norm(r[i] - r[j]);
                            if(cur < md) {
                                md = cur;
                                a = i;
                                b = j;
                            }
                        }
                    }
                }
            }
        }
        return std::pair{a, b};
    }
}

#ifndef CP_ALGO_GEOMETRY_CLOSEST_PAIR_HPP
#define CP_ALGO_GEOMETRY_CLOSEST_PAIR_HPP
#include "../random/rng.hpp"
#include "../util/big_alloc.hpp"
#include "point.hpp"
#include <vector>
#include <map>
namespace cp_algo::geometry{auto closest_pair(auto const&r){using point=std::decay_t<decltype(r[0])>;size_t n=size(r);int64_t md=1e18;for(size_t i=0;i<n/100;i++){auto A=random::rng()%n;auto B=random::rng()%n;if(A!=B){md=std::min(md,norm(r[A]-r[B]));if(md==0){return std::pair{A,B};}}}big_map<point,big_vector<size_t>>neigs;md=(int64_t)ceil(sqrt((double)md));for(size_t i=0;i<n;i++){neigs[r[i]/md].push_back(i);}size_t a=0,b=1;md=norm(r[a]-r[b]);for(auto&[p,id]:neigs){for(int dx:{-1,0,1}){for(int dy:{-1,0,1}){auto pp=p+point{dx,dy};if(!neigs.count(pp)){continue;}for(size_t i:neigs[pp]){for(size_t j:id){if(j==i){break;}int64_t cur=norm(r[i]-r[j]);if(cur<md){md=cur;a=i;b=j;}}}}}}return std::pair{a,b};}}
#endif
#line 1 "cp-algo/geometry/closest_pair.hpp"
#line 1 "cp-algo/random/rng.hpp"
#include <chrono>
#include <random>
namespace cp_algo::random{std::mt19937_64 gen(std::chrono::steady_clock::now().time_since_epoch().count());uint64_t rng(){return gen();}}
#line 1 "cp-algo/util/big_alloc.hpp"
#include <set>
#include <map>
#include <deque>
#include <stack>
#include <queue>
#include <vector>
#include <string>
#include <cstddef>
#include <iostream>
#include <generator>
#include <forward_list>
#if defined(__linux__) || defined(__unix__) || (defined(__APPLE__) && defined(__MACH__))
#  define CP_ALGO_USE_MMAP 1
#  include <sys/mman.h>
#else
#  define CP_ALGO_USE_MMAP 0
#endif
namespace cp_algo{template<typename T,size_t Align=32>class big_alloc{static_assert(Align>=alignof(void*),"Align must be at least pointer-size");static_assert(std::popcount(Align)==1,"Align must be a power of two");public:using value_type=T;template<class U>struct rebind{using other=big_alloc<U,Align>;};constexpr bool operator==(const big_alloc&)const=default;constexpr bool operator!=(const big_alloc&)const=default;big_alloc()noexcept=default;template<typename U,std::size_t A>big_alloc(const big_alloc<U,A>&)noexcept{}[[nodiscard]]T*allocate(std::size_t n){std::size_t padded=round_up(n*sizeof(T));std::size_t align=std::max<std::size_t>(alignof(T),Align);
#if CP_ALGO_USE_MMAP
if(padded>=MEGABYTE){void*raw=mmap(nullptr,padded,PROT_READ|PROT_WRITE,MAP_PRIVATE|MAP_ANONYMOUS,-1,0);madvise(raw,padded,MADV_HUGEPAGE);madvise(raw,padded,MADV_POPULATE_WRITE);return static_cast<T*>(raw);}
#endif
return static_cast<T*>(::operator new(padded,std::align_val_t(align)));}void deallocate(T*p,std::size_t n)noexcept{if(!p)return;std::size_t padded=round_up(n*sizeof(T));std::size_t align=std::max<std::size_t>(alignof(T),Align);
#if CP_ALGO_USE_MMAP
if(padded>=MEGABYTE){munmap(p,padded);return;}
#endif
::operator delete(p,padded,std::align_val_t(align));}private:static constexpr std::size_t MEGABYTE=1<<20;static constexpr std::size_t round_up(std::size_t x)noexcept{return(x+Align-1)/Align*Align;}};template<typename T>using big_vector=std::vector<T,big_alloc<T>>;template<typename T>using big_basic_string=std::basic_string<T,std::char_traits<T>,big_alloc<T>>;template<typename T>using big_deque=std::deque<T,big_alloc<T>>;template<typename T>using big_stack=std::stack<T,big_deque<T>>;template<typename T>using big_queue=std::queue<T,big_deque<T>>;template<typename T>using big_priority_queue=std::priority_queue<T,big_vector<T>>;template<typename T>using big_forward_list=std::forward_list<T,big_alloc<T>>;using big_string=big_basic_string<char>;template<typename Key,typename Value,typename Compare=std::less<Key>>using big_map=std::map<Key,Value,Compare,big_alloc<std::pair<const Key,Value>>>;template<typename T,typename Compare=std::less<T>>using big_multiset=std::multiset<T,Compare,big_alloc<T>>;template<typename T,typename Compare=std::less<T>>using big_set=std::set<T,Compare,big_alloc<T>>;template<typename Ref,typename V=void>using big_generator=std::generator<Ref,V,big_alloc<std::byte>>;}namespace std::ranges{template<typename Ref,typename V>elements_of(cp_algo::big_generator<Ref,V>&&)->elements_of<cp_algo::big_generator<Ref,V>&&,cp_algo::big_alloc<std::byte>>;}
#line 1 "cp-algo/geometry/point.hpp"
#line 1 "cp-algo/util/complex.hpp"
#line 4 "cp-algo/util/complex.hpp"
#include <cmath>
#include <type_traits>
#line 1 "cp-algo/util/simd.hpp"
#include <experimental/simd>
#include <cstdint>
#line 6 "cp-algo/util/simd.hpp"
#include <memory>
#if defined(__x86_64__) && !defined(CP_ALGO_DISABLE_AVX2)
#define CP_ALGO_SIMD_AVX2_TARGET _Pragma("GCC target(\"avx2\")")
#else
#define CP_ALGO_SIMD_AVX2_TARGET
#endif
#define CP_ALGO_SIMD_PRAGMA_PUSH \
_Pragma("GCC push_options")\CP_ALGO_SIMD_AVX2_TARGETCP_ALGO_SIMD_PRAGMA_PUSHnamespace cp_algo{template<typename T,size_t len>using simd[[gnu::vector_size(len*sizeof(T))]]=T;using u64x8=simd<uint64_t,8>;using u32x16=simd<uint32_t,16>;using i64x4=simd<int64_t,4>;using u64x4=simd<uint64_t,4>;using u32x8=simd<uint32_t,8>;using u16x16=simd<uint16_t,16>;using i32x4=simd<int32_t,4>;using u32x4=simd<uint32_t,4>;using u16x8=simd<uint16_t,8>;using u16x4=simd<uint16_t,4>;using i16x4=simd<int16_t,4>;using u8x32=simd<uint8_t,32>;using u8x8=simd<uint8_t,8>;using u8x4=simd<uint8_t,4>;using dx4=simd<double,4>;inline dx4 abs(dx4 a){return dx4{std::abs(a[0]),std::abs(a[1]),std::abs(a[2]),std::abs(a[3])};}static constexpr dx4 magic=dx4()+(3ULL<<51);inline i64x4 lround(dx4 x){return i64x4(x+magic)-i64x4(magic);}inline dx4 to_double(i64x4 x){return dx4(x+i64x4(magic))-magic;}inline dx4 round(dx4 a){return dx4{std::nearbyint(a[0]),std::nearbyint(a[1]),std::nearbyint(a[2]),std::nearbyint(a[3])};}inline u64x4 low32(u64x4 x){return x&uint32_t(-1);}inline auto swap_bytes(auto x){return decltype(x)(__builtin_shufflevector(u32x8(x),u32x8(x),1,0,3,2,5,4,7,6));}inline u64x4 montgomery_reduce(u64x4 x,uint32_t mod,uint32_t imod){
#ifdef __AVX2__
auto x_ninv=u64x4(_mm256_mul_epu32(__m256i(x),__m256i()+imod));x+=u64x4(_mm256_mul_epu32(__m256i(x_ninv),__m256i()+mod));
#else
auto x_ninv=u64x4(u32x8(low32(x))*imod);x+=x_ninv*uint64_t(mod);
#endif
return swap_bytes(x);}inline u64x4 montgomery_mul(u64x4 x,u64x4 y,uint32_t mod,uint32_t imod){
#ifdef __AVX2__
return montgomery_reduce(u64x4(_mm256_mul_epu32(__m256i(x),__m256i(y))),mod,imod);
#else
return montgomery_reduce(x*y,mod,imod);
#endif
}inline u32x8 montgomery_mul(u32x8 x,u32x8 y,uint32_t mod,uint32_t imod){return u32x8(montgomery_mul(u64x4(x),u64x4(y),mod,imod))|u32x8(swap_bytes(montgomery_mul(u64x4(swap_bytes(x)),u64x4(swap_bytes(y)),mod,imod)));}inline dx4 rotate_right(dx4 x){static constexpr u64x4 shuffler={3,0,1,2};return __builtin_shuffle(x,shuffler);}template<std::size_t Align=32>inline bool is_aligned(const auto*p)noexcept{return(reinterpret_cast<std::uintptr_t>(p)%Align)==0;}template<class Target>inline Target&vector_cast(auto&&p){return*reinterpret_cast<Target*>(std::assume_aligned<alignof(Target)>(&p));}}
#pragma GCC pop_options
#line 7 "cp-algo/util/complex.hpp"
CP_ALGO_SIMD_PRAGMA_PUSHnamespace cp_algo{template<typename T>struct complex{using value_type=T;T x,y;inline constexpr complex():x(),y(){}inline constexpr complex(T const&x):x(x),y(){}inline constexpr complex(T const&x,T const&y):x(x),y(y){}inline complex&operator*=(T const&t){x*=t;y*=t;return*this;}inline complex&operator/=(T const&t){x/=t;y/=t;return*this;}inline complex operator*(T const&t)const{return complex(*this)*=t;}inline complex operator/(T const&t)const{return complex(*this)/=t;}inline complex&operator+=(complex const&t){x+=t.x;y+=t.y;return*this;}inline complex&operator-=(complex const&t){x-=t.x;y-=t.y;return*this;}inline complex operator*(complex const&t)const{return{x*t.x-y*t.y,x*t.y+y*t.x};}inline complex operator/(complex const&t)const{return*this*t.conj()/t.norm();}inline complex operator+(complex const&t)const{return complex(*this)+=t;}inline complex operator-(complex const&t)const{return complex(*this)-=t;}inline complex&operator*=(complex const&t){return*this=*this*t;}inline complex&operator/=(complex const&t){return*this=*this/t;}inline complex operator-()const{return{-x,-y};}inline complex conj()const{return{x,-y};}inline T norm()const{return x*x+y*y;}inline T abs()const{return std::sqrt(norm());}inline T const real()const{return x;}inline T const imag()const{return y;}inline T&real(){return x;}inline T&imag(){return y;}inline static constexpr complex polar(T r,T theta){return{T(r*cos(theta)),T(r*sin(theta))};}inline auto operator<=>(complex const&t)const=default;};template<typename T>inline complex<T>conj(complex<T>const&x){return x.conj();}template<typename T>inline T norm(complex<T>const&x){return x.norm();}template<typename T>inline T abs(complex<T>const&x){return x.abs();}template<typename T>inline T&real(complex<T>&x){return x.real();}template<typename T>inline T&imag(complex<T>&x){return x.imag();}template<typename T>inline T const real(complex<T>const&x){return x.real();}template<typename T>inline T const imag(complex<T>const&x){return x.imag();}template<typename T>inline constexpr complex<T>polar(T r,T theta){return complex<T>::polar(r,theta);}template<typename T>inline std::ostream&operator<<(std::ostream&out,complex<T>const&x){return out<<x.real()<<' '<<x.imag();}}
#pragma GCC pop_options
#line 5 "cp-algo/geometry/point.hpp"
namespace cp_algo::geometry{template<typename ftype>struct point_t:complex<ftype>{using Base=complex<ftype>;using Base::Base;point_t(Base const&t):Base(t){}auto operator<=>(point_t const&t)const{return std::pair{y(),-x()}<=>std::pair{t.y(),-t.x()};}ftype x()const{return Base::real();}ftype y()const{return Base::imag();}point_t cmul(point_t const&t)const{return conj(*this)*t;}ftype dot(point_t const&t)const{return cmul(t).x();}ftype cross(point_t const&t)const{return cmul(t).y();}static constexpr point_t O={0,0};int half()const{return*this<O?-1:*this==O?0:1;}static bool ccw(point_t const&a,point_t const&b){return a.cross(b)>0;}static bool ccw_abs(point_t const&a,point_t const&b){return std::tuple{a.half(),(ftype)0,norm(a)}<std::tuple{b.half(),a.cross(b),norm(b)};}void read(){ftype _x,_y;std::cin>>_x>>_y;*this={_x,_y};}void print()const{std::cout<<x()<<' '<<y()<<"\n";}};}
#line 8 "cp-algo/geometry/closest_pair.hpp"
namespace cp_algo::geometry{auto closest_pair(auto const&r){using point=std::decay_t<decltype(r[0])>;size_t n=size(r);int64_t md=1e18;for(size_t i=0;i<n/100;i++){auto A=random::rng()%n;auto B=random::rng()%n;if(A!=B){md=std::min(md,norm(r[A]-r[B]));if(md==0){return std::pair{A,B};}}}big_map<point,big_vector<size_t>>neigs;md=(int64_t)ceil(sqrt((double)md));for(size_t i=0;i<n;i++){neigs[r[i]/md].push_back(i);}size_t a=0,b=1;md=norm(r[a]-r[b]);for(auto&[p,id]:neigs){for(int dx:{-1,0,1}){for(int dy:{-1,0,1}){auto pp=p+point{dx,dy};if(!neigs.count(pp)){continue;}for(size_t i:neigs[pp]){for(size_t j:id){if(j==i){break;}int64_t cur=norm(r[i]-r[j]);if(cur<md){md=cur;a=i;b=j;}}}}}}return std::pair{a,b};}}
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