#pragma GCC optimize("Ofast")

#include <cassert>
#include <cstdio>
#include <numeric>
#include <utility>
#include <vector>
#include <algorithm>

using namespace std;

using Int = long long;

template <unsigned M_> struct ModInt {
  static constexpr unsigned M = M_;
  unsigned x;
  constexpr ModInt() : x(0U) {}
  constexpr ModInt(unsigned x_) : x(x_ % M) {}
  constexpr ModInt(unsigned long long x_) : x(x_ % M) {}
  constexpr ModInt(int x_) : x(((x_ %= static_cast<int>(M)) < 0) ? (x_ + static_cast<int>(M)) : x_) {}
  constexpr ModInt(long long x_) : x(((x_ %= static_cast<long long>(M)) < 0) ? (x_ + static_cast<long long>(M)) : x_) {}
  ModInt &operator+=(const ModInt &a) { x = ((x += a.x) >= M) ? (x - M) : x; return *this; }
  ModInt &operator-=(const ModInt &a) { x = ((x -= a.x) >= M) ? (x + M) : x; return *this; }
  ModInt &operator*=(const ModInt &a) { x = (static_cast<unsigned long long>(x) * a.x) % M; return *this; }
  ModInt &operator/=(const ModInt &a) { return (*this *= a.inv()); }
  ModInt inv() const {
    unsigned a = M, b = x; int y = 0, z = 1;
    for (; b; ) { const unsigned q = a / b; const unsigned c = a - q * b; a = b; b = c; const int w = y - static_cast<int>(q) * z; y = z; z = w; }
    assert(a == 1U); return ModInt(y);
  }
  ModInt operator+() const { return *this; }
  ModInt operator-() const { ModInt a; a.x = x ? (M - x) : 0U; return a; }
  ModInt operator+(const ModInt &a) const { return (ModInt(*this) += a); }
  ModInt operator-(const ModInt &a) const { return (ModInt(*this) -= a); }
  ModInt operator*(const ModInt &a) const { return (ModInt(*this) *= a); }
  ModInt operator/(const ModInt &a) const { return (ModInt(*this) /= a); }
  template <class T> friend ModInt operator+(T a, const ModInt &b) { return (ModInt(a) += b); }
  template <class T> friend ModInt operator-(T a, const ModInt &b) { return (ModInt(a) -= b); }
  template <class T> friend ModInt operator*(T a, const ModInt &b) { return (ModInt(a) *= b); }
  template <class T> friend ModInt operator/(T a, const ModInt &b) { return (ModInt(a) /= b); }
  explicit operator bool() const { return x; }
  bool operator==(const ModInt &a) const { return (x == a.x); }
  bool operator!=(const ModInt &a) const { return (x != a.x); }
};

constexpr unsigned MO = 998244353U;
constexpr unsigned MO2 = 2U * MO;
constexpr int FFT_MAX = 23;
using Mint = ModInt<MO>;
constexpr Mint FFT_ROOTS[FFT_MAX + 1] = {1U, 998244352U, 911660635U, 372528824U, 929031873U, 452798380U, 922799308U, 781712469U, 476477967U, 166035806U, 258648936U, 584193783U, 63912897U, 350007156U, 666702199U, 968855178U, 629671588U, 24514907U, 996173970U, 363395222U, 565042129U, 733596141U, 267099868U, 15311432U};
constexpr Mint INV_FFT_ROOTS[FFT_MAX + 1] = {1U, 998244352U, 86583718U, 509520358U, 337190230U, 87557064U, 609441965U, 135236158U, 304459705U, 685443576U, 381598368U, 335559352U, 129292727U, 358024708U, 814576206U, 708402881U, 283043518U, 3707709U, 121392023U, 704923114U, 950391366U, 428961804U, 382752275U, 469870224U};
constexpr Mint FFT_RATIOS[FFT_MAX] = {911660635U, 509520358U, 369330050U, 332049552U, 983190778U, 123842337U, 238493703U, 975955924U, 603855026U, 856644456U, 131300601U, 842657263U, 730768835U, 942482514U, 806263778U, 151565301U, 510815449U, 503497456U, 743006876U, 741047443U, 56250497U, 867605899U};
constexpr Mint INV_FFT_RATIOS[FFT_MAX] = {86583718U, 372528824U, 373294451U, 645684063U, 112220581U, 692852209U, 155456985U, 797128860U, 90816748U, 860285882U, 927414960U, 354738543U, 109331171U, 293255632U, 535113200U, 308540755U, 121186627U, 608385704U, 438932459U, 359477183U, 824071951U, 103369235U};

void fft(Mint *as, int n) {
  assert(!(n & (n - 1))); assert(1 <= n); assert(n <= 1 << FFT_MAX);
  int m = n;
  if (m >>= 1) {
    for (int i = 0; i < m; ++i) {
      const unsigned x = as[i + m].x;
      as[i + m].x = as[i].x + MO - x;
      as[i].x += x;
    }
  }
  if (m >>= 1) {
    Mint prod = 1U;
    for (int h = 0, i0 = 0; i0 < n; i0 += (m << 1)) {
      for (int i = i0; i < i0 + m; ++i) {
        const unsigned x = (prod * as[i + m]).x;  // < MO
        as[i + m].x = as[i].x + MO - x;  // < 3 MO
        as[i].x += x;  // < 3 MO
      }
      prod *= FFT_RATIOS[__builtin_ctz(++h)];
    }
  }
  for (; m; ) {
    if (m >>= 1) {
      Mint prod = 1U;
      for (int h = 0, i0 = 0; i0 < n; i0 += (m << 1)) {
        for (int i = i0; i < i0 + m; ++i) {
          const unsigned x = (prod * as[i + m]).x;  // < MO
          as[i + m].x = as[i].x + MO - x;  // < 4 MO
          as[i].x += x;  // < 4 MO
        }
        prod *= FFT_RATIOS[__builtin_ctz(++h)];
      }
    }
    if (m >>= 1) {
      Mint prod = 1U;
      for (int h = 0, i0 = 0; i0 < n; i0 += (m << 1)) {
        for (int i = i0; i < i0 + m; ++i) {
          const unsigned x = (prod * as[i + m]).x;  // < MO
          as[i].x = (as[i].x >= MO2) ? (as[i].x - MO2) : as[i].x;  // < 2 MO
          as[i + m].x = as[i].x + MO - x;  // < 3 MO
          as[i].x += x;  // < 3 MO
        }
        prod *= FFT_RATIOS[__builtin_ctz(++h)];
      }
    }
  }
  for (int i = 0; i < n; ++i) {
    as[i].x = (as[i].x >= MO2) ? (as[i].x - MO2) : as[i].x;  // < 2 MO
    as[i].x = (as[i].x >= MO) ? (as[i].x - MO) : as[i].x;  // < MO
  }
}

void invFft(Mint *as, int n) {
  assert(!(n & (n - 1))); assert(1 <= n); assert(n <= 1 << FFT_MAX);
  int m = 1;
  if (m < n >> 1) {
    Mint prod = 1U;
    for (int h = 0, i0 = 0; i0 < n; i0 += (m << 1)) {
      for (int i = i0; i < i0 + m; ++i) {
        const unsigned long long y = as[i].x + MO - as[i + m].x;  // < 2 MO
        as[i].x += as[i + m].x;  // < 2 MO
        as[i + m].x = (prod.x * y) % MO;  // < MO
      }
      prod *= INV_FFT_RATIOS[__builtin_ctz(++h)];
    }
    m <<= 1;
  }
  for (; m < n >> 1; m <<= 1) {
    Mint prod = 1U;
    for (int h = 0, i0 = 0; i0 < n; i0 += (m << 1)) {
      for (int i = i0; i < i0 + (m >> 1); ++i) {
        const unsigned long long y = as[i].x + MO2 - as[i + m].x;  // < 4 MO
        as[i].x += as[i + m].x;  // < 4 MO
        as[i].x = (as[i].x >= MO2) ? (as[i].x - MO2) : as[i].x;  // < 2 MO
        as[i + m].x = (prod.x * y) % MO;  // < MO
      }
      for (int i = i0 + (m >> 1); i < i0 + m; ++i) {
        const unsigned long long y = as[i].x + MO - as[i + m].x;  // < 2 MO
        as[i].x += as[i + m].x;  // < 2 MO
        as[i + m].x = (prod.x * y) % MO;  // < MO
      }
      prod *= INV_FFT_RATIOS[__builtin_ctz(++h)];
    }
  }
  if (m < n) {
    for (int i = 0; i < m; ++i) {
      const unsigned y = as[i].x + MO2 - as[i + m].x;  // < 4 MO
      as[i].x += as[i + m].x;  // < 4 MO
      as[i + m].x = y;  // < 4 MO
    }
  }
  const Mint invN = Mint(n).inv();
  for (int i = 0; i < n; ++i) {
    as[i] *= invN;
  }
}

void fft(vector<Mint> &as) {
  fft(as.data(), as.size());
}
void invFft(vector<Mint> &as) {
  invFft(as.data(), as.size());
}

constexpr int LIM_INV = 1 << 20;  // @
Mint inv[LIM_INV], fac[LIM_INV], invFac[LIM_INV];
struct ModIntPreparator {
  ModIntPreparator() {
    inv[1] = 1;
    for (int i = 2; i < LIM_INV; ++i) inv[i] = -((Mint::M / i) * inv[Mint::M % i]);
    fac[0] = 1;
    for (int i = 1; i < LIM_INV; ++i) fac[i] = fac[i - 1] * i;
    invFac[0] = 1;
    for (int i = 1; i < LIM_INV; ++i) invFac[i] = invFac[i - 1] * inv[i];
  }
} preparator;

static constexpr int LIM_POLY = 1 << 20;
static Mint polyWork0[LIM_POLY], polyWork1[LIM_POLY], polyWork2[LIM_POLY], polyWork3[LIM_POLY];

struct Poly : public vector<Mint> {
  Poly() {}
  explicit Poly(int n) : vector<Mint>(n) {}
  Poly(const vector<Mint> &vec) : vector<Mint>(vec) {}
  Poly(std::initializer_list<Mint> il) : vector<Mint>(il) {}
  int size() const { return vector<Mint>::size(); }
  Mint at(long long k) const { return (0 <= k && k < size()) ? (*this)[k] : 0U; }
  int ord() const { for (int i = 0; i < size(); ++i) if ((*this)[i]) return i; return -1; }
  int deg() const { for (int i = size(); --i >= 0; ) if ((*this)[i]) return i; return -1; }
  Poly mod(int n) const { return Poly(vector<Mint>(data(), data() + min(n, size()))); }

  Poly &operator+=(const Poly &fs) {
    if (size() < fs.size()) resize(fs.size());
    for (int i = 0; i < fs.size(); ++i) (*this)[i] += fs[i];
    return *this;
  }
  Poly &operator-=(const Poly &fs) {
    if (size() < fs.size()) resize(fs.size());
    for (int i = 0; i < fs.size(); ++i) (*this)[i] -= fs[i];
    return *this;
  }
  Poly &operator*=(const Poly &fs) {
    if (empty() || fs.empty()) return *this = {};
    const int nt = size(), nf = fs.size();
    int n = 1;
    for (; n < nt + nf - 1; n <<= 1) {}
    assert(n <= LIM_POLY);
    resize(n);
    fft(data(), n);
    __builtin_memcpy(polyWork0, fs.data(), nf * sizeof(Mint));
    __builtin_memset(polyWork0 + nf, 0, (n - nf) * sizeof(Mint));
    fft(polyWork0, n);
    for (int i = 0; i < n; ++i) (*this)[i] *= polyWork0[i];
    invFft(data(), n);
    resize(nt + nf - 1);
    return *this;
  }
  Poly &operator/=(const Poly &fs) {
    const int m = deg(), n = fs.deg();
    assert(n != -1);
    if (m < n) return *this = {};
    Poly tsRev(m - n + 1), fsRev(min(m - n, n) + 1);
    for (int i = 0; i <= m - n; ++i) tsRev[i] = (*this)[m - i];
    for (int i = 0, i0 = min(m - n, n); i <= i0; ++i) fsRev[i] = fs[n - i];
    const Poly qsRev = tsRev.div(fsRev, m - n + 1);
    resize(m - n + 1);
    for (int i = 0; i <= m - n; ++i) (*this)[i] = qsRev[m - n - i];
    return *this;
  }
  Poly &operator%=(const Poly &fs) {
    const Poly qs = *this / fs;
    *this -= fs * qs;
    resize(deg() + 1);
    return *this;
  }
  Poly &operator*=(const Mint &a) {
    for (int i = 0; i < size(); ++i) (*this)[i] *= a;
    return *this;
  }
  Poly &operator/=(const Mint &a) {
    const Mint b = a.inv();
    for (int i = 0; i < size(); ++i) (*this)[i] *= b;
    return *this;
  }
  Poly operator+() const { return *this; }
  Poly operator-() const {
    Poly fs(size());
    for (int i = 0; i < size(); ++i) fs[i] = -(*this)[i];
    return fs;
  }
  Poly operator+(const Poly &fs) const { return (Poly(*this) += fs); }
  Poly operator-(const Poly &fs) const { return (Poly(*this) -= fs); }
  Poly operator*(const Poly &fs) const { return (Poly(*this) *= fs); }
  Poly operator/(const Poly &fs) const { return (Poly(*this) /= fs); }
  Poly operator%(const Poly &fs) const { return (Poly(*this) %= fs); }
  Poly operator*(const Mint &a) const { return (Poly(*this) *= a); }
  Poly operator/(const Mint &a) const { return (Poly(*this) /= a); }
  friend Poly operator*(const Mint &a, const Poly &fs) { return fs * a; }

  Poly inv(int n) const {
    assert(!empty()); assert((*this)[0]); assert(1 <= n);
    assert(n == 1 || 1 << (32 - __builtin_clz(n - 1)) <= LIM_POLY);
    Poly fs(n);
    fs[0] = (*this)[0].inv();
    for (int m = 1; m < n; m <<= 1) {
      __builtin_memcpy(polyWork0, data(), min(m << 1, size()) * sizeof(Mint));
      __builtin_memset(polyWork0 + min(m << 1, size()), 0, ((m << 1) - min(m << 1, size())) * sizeof(Mint));
      fft(polyWork0, m << 1);
      __builtin_memcpy(polyWork1, fs.data(), min(m << 1, n) * sizeof(Mint));
      __builtin_memset(polyWork1 + min(m << 1, n), 0, ((m << 1) - min(m << 1, n)) * sizeof(Mint));
      fft(polyWork1, m << 1);
      for (int i = 0; i < m << 1; ++i) polyWork0[i] *= polyWork1[i];
      invFft(polyWork0, m << 1);
      __builtin_memset(polyWork0, 0, m * sizeof(Mint));
      fft(polyWork0, m << 1);
      for (int i = 0; i < m << 1; ++i) polyWork0[i] *= polyWork1[i];
      invFft(polyWork0, m << 1);
      for (int i = m, i0 = min(m << 1, n); i < i0; ++i) fs[i] = -polyWork0[i];
    }
    return fs;
  }
  Poly div(const Poly &fs, int n) const {
    assert(!fs.empty()); assert(fs[0]); assert(1 <= n);
    if (n == 1) return {at(0) / fs[0]};
    const int m = 1 << (31 - __builtin_clz(n - 1));
    assert(m << 1 <= LIM_POLY);
    Poly gs = fs.inv(m);
    gs.resize(m << 1);
    fft(gs.data(), m << 1);
    __builtin_memcpy(polyWork0, data(), min(m, size()) * sizeof(Mint));
    __builtin_memset(polyWork0 + min(m, size()), 0, ((m << 1) - min(m, size())) * sizeof(Mint));
    fft(polyWork0, m << 1);
    for (int i = 0; i < m << 1; ++i) polyWork0[i] *= gs[i];
    invFft(polyWork0, m << 1);
    Poly hs(n);
    __builtin_memcpy(hs.data(), polyWork0, m * sizeof(Mint));
    __builtin_memset(polyWork0 + m, 0, m * sizeof(Mint));
    fft(polyWork0, m << 1);
    __builtin_memcpy(polyWork1, fs.data(), min(m << 1, fs.size()) * sizeof(Mint));
    __builtin_memset(polyWork1 + min(m << 1, fs.size()), 0, ((m << 1) - min(m << 1, fs.size())) * sizeof(Mint));
    fft(polyWork1, m << 1);
    for (int i = 0; i < m << 1; ++i) polyWork0[i] *= polyWork1[i];
    invFft(polyWork0, m << 1);
    __builtin_memset(polyWork0, 0, m * sizeof(Mint));
    for (int i = m, i0 = min(m << 1, size()); i < i0; ++i) polyWork0[i] -= (*this)[i];
    fft(polyWork0, m << 1);
    for (int i = 0; i < m << 1; ++i) polyWork0[i] *= gs[i];
    invFft(polyWork0, m << 1);
    for (int i = m; i < n; ++i) hs[i] = -polyWork0[i];
    return hs;
  }
  Poly shift(const Mint &a) const {
    if (empty()) return {};
    const int n = size();
    int m = 1;
    for (; m < n; m <<= 1) {}
    for (int i = 0; i < n; ++i) polyWork0[i] = fac[i] * (*this)[i];
    __builtin_memset(polyWork0 + n, 0, ((m << 1) - n) * sizeof(Mint));
    fft(polyWork0, m << 1);
    {
      Mint aa = 1;
      for (int i = 0; i < n; ++i) { polyWork1[n - 1 - i] = invFac[i] * aa; aa *= a; }
    }
    __builtin_memset(polyWork1 + n, 0, ((m << 1) - n) * sizeof(Mint));
    fft(polyWork1, m << 1);
    for (int i = 0; i < m << 1; ++i) polyWork0[i] *= polyWork1[i];
    invFft(polyWork0, m << 1);
    Poly fs(n);
    for (int i = 0; i < n; ++i) fs[i] = invFac[i] * polyWork0[n - 1 + i];
    return fs;
  }
};

struct SubproductTree {
  int logN, n, nn;
  vector<Mint> xs, buf;
  vector<Mint *> gss;
  Poly all;
  SubproductTree(const vector<Mint> &xs_) {
    n = xs_.size();
    for (logN = 0, nn = 1; nn < n; ++logN, nn <<= 1) {}
    xs.assign(nn, 0U);
    __builtin_memcpy(xs.data(), xs_.data(), n * sizeof(Mint));
    buf.assign((logN + 1) * (nn << 1), 0U);
    gss.assign(nn << 1, nullptr);
    for (int h = 0; h <= logN; ++h) for (int u = 1 << h; u < 1 << (h + 1); ++u) {
      gss[u] = buf.data() + (h * (nn << 1) + ((u - (1 << h)) << (logN - h + 1)));
    }
    for (int i = 0; i < nn; ++i) {
      gss[nn + i][0] = -xs[i] + 1;
      gss[nn + i][1] = -xs[i] - 1;
    }
    if (nn == 1) gss[1][1] += 2;
    for (int h = logN; --h >= 0; ) {
      const int m = 1 << (logN - h);
      for (int u = 1 << (h + 1); --u >= 1 << h; ) {
        for (int i = 0; i < m; ++i) gss[u][i] = gss[u << 1][i] * gss[u << 1 | 1][i];
        __builtin_memcpy(gss[u] + m, gss[u], m * sizeof(Mint));
        invFft(gss[u] + m, m);
        if (h > 0) {
          gss[u][m] -= 2;
          const Mint a = FFT_ROOTS[logN - h + 1];
          Mint aa = 1;
          for (int i = m; i < m << 1; ++i) { gss[u][i] *= aa; aa *= a; };
          fft(gss[u] + m, m);
        }
      }
    }
    all.resize(nn + 1);
    all[0] = 1;
    for (int i = 1; i < nn; ++i) all[i] = gss[1][nn + nn - i];
    all[nn] = gss[1][nn] - 1;
  }
};

Mint binom(Int n, Int k) {
  if (n < 0) {
    if (k >= 0) {
      return ((k & 1) ? -1 : +1) * binom(-n + k - 1, k);
    } else if (n - k >= 0) {
      return (((n - k) & 1) ? -1 : +1) * binom(-k - 1, n - k);
    } else {
      return 0;
    }
  } else {
    if (0 <= k && k <= n) {
      assert(n < LIM_INV);
      return fac[n] * invFac[k] * invFac[n - k];
    } else {
      return 0;
    }
  }
}


Mint two[LIM_INV], invTwo[LIM_INV];

int N, M;
vector<Mint> P, Q;

Poly comp1(Poly fs, int n) {
  reverse(fs.begin(), fs.end());
  fs = fs.shift(inv[4]);
  Poly gs(2 * fs.size() - 1);
  for (int i = 0; i < fs.size(); ++i) gs[2 * i] = (i&1?-1:+1) * fs[i];
  gs = gs.shift(inv[2]);
  for (int i = 1; i < gs.size(); i += 2) gs[i] = -gs[i];
  Poly bns(n);
  for (int i = 0; i < bns.size(); ++i) bns[i] = binom(-(fs.size() - 1), i) * (i&1?-1:+1);
  return (bns * gs).mod(n);
}

Poly comp0(Poly fs, int n) {
  reverse(fs.begin(), fs.end());
  fs = fs.shift(1);
  for (int i = 1; i < fs.size(); i += 2) fs[i] = -fs[i];
  Poly bns(n);
  for (int i = 0; i < bns.size(); ++i) bns[i] = binom(-(fs.size() - 1), i) * (i&1?-1:+1);
  return (bns * fs).mod(n);
}

Mint fast2() {
  Poly LOG(N + 1);
  for (int i = 1; i < LOG.size(); ++i) LOG[i] = inv[i] * ((i-1)&1?-1:+1) * two[i];
  Poly pss[2], qss[2];
  for (int s = 0; s < 2; ++s) {
    Poly ps(N);
    for (int n = 0; n < N; ++n) ps[n] = P[n] * (s ? n : 1);
    pss[s] = comp1(ps, N + 1);
  }
  for (int s = 0; s < 2; ++s) {
    Poly qs(M);
    for (int m = 0; m < M; ++m) qs[m] = Q[m] * (s ? m : 1);
    qss[s] = comp0(qs, N + 1);
  }
  const Poly prod10 = (pss[1] * qss[0]).mod(N + 1);
  const Poly prod01 = (pss[0] * qss[1]).mod(N + 1);
  const Poly prod00 = (pss[0] * qss[0]).mod(N + 1);
  Poly gs0 = 2 * prod10 + prod01 + prod00;
  Poly gs1 = inv[2] * (prod10 + prod01 + prod00);
  Poly gs2 = prod00;
  for (int i = 1; i < gs0.size(); ++i) gs0[i] += gs0[i - 1];
  for (int i = 1; i < gs1.size(); ++i) gs1[i] += gs1[i - 1];
  for (int i = 1; i < gs1.size(); ++i) gs1[i] += gs1[i - 1];
  for (int i = 1; i < gs2.size(); ++i) gs2[i] += gs2[i - 1];
  gs0.insert(gs0.begin(), 0);
  gs2.insert(gs2.begin(), 0);
  const Mint ans = (gs0 - LOG * (gs1 + gs2)).at(N);
  return ans;
}


main() {
  two[0] = invTwo[0] = 1;
  #pragma unroll
  for (unsigned i = 1; i < LIM_INV; ++i) {
    two[i] = two[i - 1] * 2; invTwo[i] = invTwo[i - 1] * inv[2];
  }

  for (; ~scanf("%d%d", &N, &M);) {
    P.resize(N); for (unsigned n = 0; n ^ N; ++n) scanf("%u", &P[n].x);
    Q.resize(M); for (unsigned m = 0; m ^ M; ++m) scanf("%u", &Q[m].x);

    const Mint ans = fast2();
    printf("%u\n", ans.x);
  }
}