struct poly { vector data; poly(int deg = 0) : data(1 + deg) {} poly(initializer_list _data) : data(_data) {} int size() const { return sz(data); } void trim() { for (ll& x : data) x = (x % mod + mod) % mod; while (size() > 1 && data.back() == 0) data.pop_back(); } ll& operator[](int x) { return data[x]; } const ll& operator[](int x) const { return data[x]; } ll operator()(int x) const { ll res = 0; for (int i = size() - 1; i >= 0; i--) res = (res * x + data[i]) % mod; return res % mod; } poly& operator+=(const poly& o) { if (size() < o.size()) data.resize(o.size()); for (int i = 0; i < o.size(); i++) data[i] = (data[i] + o[i]) % mod; return *this; } poly operator*(const poly& o) const { poly res(size() + o.size() - 1); for (int i = 0; i < size(); i++) { for (int j = 0; j < o.size(); j++) { res[i + j] += (data[i] * o[j]) % mod; }} res.trim(); return res; } //return p(x+a) poly operator<<(ll a) const { poly res(size() - 1); for (int i = size() - 1; i >= 0; i--) { for (int j = size() - i - 1; j >= 1; j--) res[j] = (res[j] * a + res[j - 1]) % mod; res[0] = (res[0] * a + data[i]) % mod; } return res; } pair divmod(const poly& d) const { int i = size() - d.size(); if (i <= 0) return {{}, *this}; poly s(i + 1), r = *this; ll inv = multInv(d.data.back(), mod); for (; i >= 0; i--) { s[i] = (r.data.back() * inv) % mod; r.data.pop_back(); for (int j = 0; i + j < r.size(); j++) { r[i + j] = (r.data[i + j] - s[i] * d[j]) % mod; }} s.trim(); r.trim(); return {s, r}; } };