#include <bits/stdc++.h>
using namespace std;
template <int MOD_>
struct modnum {
  static constexpr int MOD = MOD_;
  static_assert(MOD_ > 0, "MOD must be positive");

 private:
  using ll = long long;
  int v;
  static int minv(int a, int m) {
    a %= m;
    assert(a);
    return a == 1 ? 1 : int(m - ll(minv(m, a)) * ll(m) / a);
  }

 public:
  modnum() : v(0) {}
  modnum(ll v_) : v(int(v_ % MOD)) {
    if (v < 0) v += MOD;
  }
  explicit operator int() const { return v; }
  friend ostream& operator<<(ostream& out, const modnum& n) {
    return out << int(n);
  }
  friend istream& operator>>(istream& in, modnum& n) {
    ll v_;
    in >> v_;
    n = modnum(v_);
    return in;
  }
  friend bool operator==(const modnum& a, const modnum& b) {
    return a.v == b.v;
  }
  friend bool operator!=(const modnum& a, const modnum& b) {
    return a.v != b.v;
  }
  modnum inv() const {
    modnum res;
    res.v = minv(v, MOD);
    return res;
  }
  modnum neg() const {
    modnum res;
    res.v = v ? MOD - v : 0;
    return res;
  }
  modnum pow(ll k) const {
    modnum res = 1, x = v;
    while (k) {
      if (k & 1) res *= x;
      x *= x;
      k >>= 1;
    }
    return res;
  }
  modnum operator-() const { return neg(); }
  modnum operator+() const { return modnum(*this); }
  modnum& operator++() {
    v++;
    if (v == MOD) v = 0;
    return *this;
  }
  modnum& operator--() {
    if (v == 0) v = MOD;
    v--;
    return *this;
  }
  modnum& operator+=(const modnum& o) {
    v += o.v;
    if (v >= MOD) v -= MOD;
    return *this;
  }
  modnum& operator-=(const modnum& o) {
    v -= o.v;
    if (v < 0) v += MOD;
    return *this;
  }
  modnum& operator*=(const modnum& o) {
    v = int(ll(v) * ll(o.v) % MOD);
    return *this;
  }
  modnum& operator/=(const modnum& o) { return *this *= o.inv(); }
  friend modnum operator++(modnum& a, int) {
    modnum r = a;
    ++a;
    return r;
  }
  friend modnum operator--(modnum& a, int) {
    modnum r = a;
    --a;
    return r;
  }
  friend modnum operator+(const modnum& a, const modnum& b) {
    return modnum(a) += b;
  }
  friend modnum operator-(const modnum& a, const modnum& b) {
    return modnum(a) -= b;
  }
  friend modnum operator*(const modnum& a, const modnum& b) {
    return modnum(a) *= b;
  }
  friend modnum operator/(const modnum& a, const modnum& b) {
    return modnum(a) /= b;
  }
};
using mint = modnum<998244353>;
vector<mint> fac, inv;
inline mint nCr(int n, int r) {
  if (r < 0 || r > n) return 0;
  if (n >= (int)fac.size()) {
    int s = fac.size();
    fac.resize(n + 1);
    inv.resize(n + 1);
    for (int i = s; i <= n; i++) fac[i] = fac[i - 1] * i;
    inv[n] = fac[n].inv();
    for (int i = n; i > s; i--) inv[i - 1] = inv[i] * i;
  }
  return fac[n] * inv[n - r] * inv[r];
}
void solve() {
  int n, k;
  cin >> n >> k;
  vector<int> a(n), b(k), pos(n);
  vector<bool> used(n, true);
  for (int i = 0; i < n; i++) {
    cin >> a[i];
    a[i]--;
    pos[a[i]] = i;
  }
  for (int i = 0; i < k; i++) {
    cin >> b[i];
    b[i]--;
    used[b[i]] = false;
  }
  mint ans = 1;
  for (int x : b) {
    int i = pos[x];
    int cnt = 0;
    if (i > 0 && used[a[i - 1]]) {
      cnt++;
    }
    if (i + 1 < n && used[a[i + 1]]) {
      cnt++;
    }
    if (cnt == 0) {
      ans = 0;
      break;
    }
    ans *= cnt;
    used[x] = true;
  }
  cout << ans << '\n';
}
int main() {
  ios::sync_with_stdio(false), cin.tie(nullptr);
  int tt = 1;
  cin >> tt;
  while (tt--) solve();
  return 0;
}
