#include <bits/stdc++.h>
using namespace std;
using lli = long long int;
template <signed M, unsigned T>
struct mod_int {
  constexpr static signed MODULO = M;
  constexpr static unsigned TABLE_SIZE = T;
  signed x;
  mod_int() : x(0) {}
  mod_int(long long y)
      : x(static_cast<signed>(y >= 0 ? y % MODULO : MODULO - (-y) % MODULO)) {}
  mod_int(int y) : x(y >= 0 ? y % MODULO : MODULO - (-y) % MODULO) {}
  mod_int& operator+=(const mod_int& rhs) {
    if ((x += rhs.x) >= MODULO) x -= MODULO;
    return *this;
  }
  mod_int& operator-=(const mod_int& rhs) {
    if ((x += MODULO - rhs.x) >= MODULO) x -= MODULO;
    return *this;
  }
  mod_int& operator*=(const mod_int& rhs) {
    x = static_cast<signed>(1LL * x * rhs.x % MODULO);
    return *this;
  }
  mod_int& operator/=(const mod_int& rhs) {
    x = static_cast<signed>((1LL * x * rhs.inv().x) % MODULO);
    return *this;
  }
  mod_int operator-() const { return mod_int(-x); }
  mod_int operator+(const mod_int& rhs) const { return mod_int(*this) += rhs; }
  mod_int operator-(const mod_int& rhs) const { return mod_int(*this) -= rhs; }
  mod_int operator*(const mod_int& rhs) const { return mod_int(*this) *= rhs; }
  mod_int operator/(const mod_int& rhs) const { return mod_int(*this) /= rhs; }
  bool operator<(const mod_int& rhs) const { return x < rhs.x; }
  mod_int inv() const {
    assert(x != 0);
    if (x <= static_cast<signed>(TABLE_SIZE)) {
      if (_inv[1].x == 0) prepare();
      return _inv[x];
    } else {
      signed a = x, b = MODULO, u = 1, v = 0, t;
      while (b) {
        t = a / b;
        a -= t * b;
        std::swap(a, b);
        u -= t * v;
        std::swap(u, v);
      }
      return mod_int(u);
    }
  }
  mod_int pow(long long t) const {
    assert(!(x == 0 && t == 0));
    mod_int e = *this, res = mod_int(1);
    for (; t; e *= e, t >>= 1)
      if (t & 1) res *= e;
    return res;
  }
  mod_int fact() {
    if (_fact[0].x == 0) prepare();
    return _fact[x];
  }
  mod_int inv_fact() {
    if (_fact[0].x == 0) prepare();
    return _inv_fact[x];
  }
  mod_int choose(mod_int y) {
    assert(y.x <= x);
    return this->fact() * y.inv_fact() * mod_int(x - y.x).inv_fact();
  }
  static mod_int _inv[TABLE_SIZE + 1];
  static mod_int _fact[TABLE_SIZE + 1];
  static mod_int _inv_fact[TABLE_SIZE + 1];
  static void prepare() {
    _inv[1] = 1;
    for (int i = 2; i <= (int)TABLE_SIZE; ++i) {
      _inv[i] = 1LL * _inv[MODULO % i].x * (MODULO - MODULO / i) % MODULO;
    }
    _fact[0] = 1;
    for (unsigned i = 1; i <= TABLE_SIZE; ++i) {
      _fact[i] = _fact[i - 1] * int(i);
    }
    _inv_fact[TABLE_SIZE] = _fact[TABLE_SIZE].inv();
    for (int i = (int)TABLE_SIZE - 1; i >= 0; --i) {
      _inv_fact[i] = _inv_fact[i + 1] * (i + 1);
    }
  }
};
template <int M, unsigned F>
std::ostream& operator<<(std::ostream& os, const mod_int<M, F>& rhs) {
  return os << rhs.x;
}
template <int M, unsigned F>
std::istream& operator>>(std::istream& is, mod_int<M, F>& rhs) {
  long long s;
  is >> s;
  rhs = mod_int<M, F>(s);
  return is;
}
template <int M, unsigned F>
mod_int<M, F> mod_int<M, F>::_inv[TABLE_SIZE + 1];
template <int M, unsigned F>
mod_int<M, F> mod_int<M, F>::_fact[TABLE_SIZE + 1];
template <int M, unsigned F>
mod_int<M, F> mod_int<M, F>::_inv_fact[TABLE_SIZE + 1];
template <int M, unsigned F>
bool operator==(const mod_int<M, F>& lhs, const mod_int<M, F>& rhs) {
  return lhs.x == rhs.x;
}
template <int M, unsigned F>
bool operator!=(const mod_int<M, F>& lhs, const mod_int<M, F>& rhs) {
  return !(lhs == rhs);
}
const int MF = 1;
const int MOD = 1000000007;
using mint = mod_int<MOD, MF>;
mint binom(int n, int r) {
  return (r < 0 || r > n || n < 0) ? 0 : mint(n).choose(r);
}
mint fact(int n) { return mint(n).fact(); }
mint inv_fact(int n) { return mint(n).inv_fact(); }
mint dp[2005][2005] = {};
vector<int> a;
map<int, set<int>> ma;
int n, m;
bool vi[2005][2005] = {};
mint calc(lli i, lli j) {
  mint& ret = dp[i][j];
  if (i >= n || j >= m) return 1;
  if (vi[i][j]) return ret;
  for (auto s = ma[a[i]].upper_bound(j - 1); s != ma[a[i]].end(); s++) {
    ret += calc(i + 1, *s + 1);
  }
  ret += calc(i + 1, j);
  vi[i][j] = true;
  return ret;
}
int main() {
  cin >> n >> m;
  vector<int> s(n);
  vector<int> t(m);
  for (lli i = 0; i < (n); i++) cin >> s[i];
  for (lli i = 0; i < (m); i++) cin >> t[i];
  a = s;
  for (lli i = 0; i < (m); i++) ma[t[i]].insert(i);
  cout << calc(0, 0) << endl;
}
