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#include "library/math/inv_mods.hpp"
#ifndef SUISEN_INV_MOD #define SUISEN_INV_MOD #include <vector> namespace suisen { template <typename mint> class inv_mods { public: inv_mods() = default; inv_mods(int n) { ensure(n); } const mint& operator[](int i) const { ensure(i); return invs[i]; } static void ensure(int n) { int sz = invs.size(); if (sz < 2) invs = { 0, 1 }, sz = 2; if (sz < n + 1) { invs.resize(n + 1); for (int i = sz; i <= n; ++i) invs[i] = mint(mod - mod / i) * invs[mod % i]; } } private: static std::vector<mint> invs; static constexpr int mod = mint::mod(); }; template <typename mint> std::vector<mint> inv_mods<mint>::invs{}; template <typename mint> std::vector<mint> get_invs(const std::vector<mint>& vs) { const int n = vs.size(); mint p = 1; for (auto& e : vs) { p *= e; assert(e != 0); } mint ip = p.inv(); std::vector<mint> rp(n + 1); rp[n] = 1; for (int i = n - 1; i >= 0; --i) { rp[i] = rp[i + 1] * vs[i]; } std::vector<mint> res(n); for (int i = 0; i < n; ++i) { res[i] = ip * rp[i + 1]; ip *= vs[i]; } return res; } } #endif // SUISEN_INV_MOD
#line 1 "library/math/inv_mods.hpp" #include <vector> namespace suisen { template <typename mint> class inv_mods { public: inv_mods() = default; inv_mods(int n) { ensure(n); } const mint& operator[](int i) const { ensure(i); return invs[i]; } static void ensure(int n) { int sz = invs.size(); if (sz < 2) invs = { 0, 1 }, sz = 2; if (sz < n + 1) { invs.resize(n + 1); for (int i = sz; i <= n; ++i) invs[i] = mint(mod - mod / i) * invs[mod % i]; } } private: static std::vector<mint> invs; static constexpr int mod = mint::mod(); }; template <typename mint> std::vector<mint> inv_mods<mint>::invs{}; template <typename mint> std::vector<mint> get_invs(const std::vector<mint>& vs) { const int n = vs.size(); mint p = 1; for (auto& e : vs) { p *= e; assert(e != 0); } mint ip = p.inv(); std::vector<mint> rp(n + 1); rp[n] = 1; for (int i = n - 1; i >= 0; --i) { rp[i] = rp[i + 1] * vs[i]; } std::vector<mint> res(n); for (int i = 0; i < n; ++i) { res[i] = ip * rp[i + 1]; ip *= vs[i]; } return res; } }