template ll qpow_m(ll b, ll p) { if (b == 0 and p != 0) return 0; if (p == 0) return 1; ll half = qpow_m(b, p / 2); if (p % 2 == 1) return (half * half % M)* b % M; else return half * half % M; } template void ntt(vector& y, bool idft) { int n = y.size(); vector rev(n); for (int i = 0; i < n; ++i) { rev[i] = rev[i >> 1] >> 1; if (i & 1) { rev[i] |= n >> 1; } } for (int i = 0; i < n; ++i) { if (i < rev[i]) { swap(y[i], y[rev[i]]); } } vector roots = { 0, 1 }; if (roots.size() < n) { int k = lsp(roots.size()); roots.resize(n); for (; (1 << k) < n; ++k) { ll e = qpow_m(31, 1 << lsp(M - 1) - k - 1); for (int i = 1 << k - 1; i < (1 << k); ++i) { roots[2 * i] = roots[i]; roots[2 * i + 1] = roots[i] * e % M; } } } for (int h = 2; h <= n; h <<= 1) { for (int j = 0; j < n; j += h) { for (int k = j; k < j + h / 2; ++k) { ll u = y[k], t = roots[k - j + h / 2] * y[k + h / 2] % M; y[k] = (u + t) % M; y[k + h / 2] = mod(u - t, M); } } } if (idft) { reverse(y.begin() + 1, y.end()); ll inv = inverse(n, M); for (int i = 0; i < n; ++i) { y[i] = y[i] * inv % M; } } } template vector multiply(const vector& a, const vector& b) { vector A(a.begin(), a.end()), B(b.begin(), b.end()); int n = 1; while (n < a.size() + b.size()) n <<= 1; A.resize(n), B.resize(n); ntt(A, false), ntt(B, false); for (int i = 0; i < n; ++i) { A[i] = A[i] * B[i] % M; } ntt(A, true); return A; }