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

template <class T, class U>
inline bool chmin(T &lhs, const U &rhs) {
  if (lhs > rhs) {
    lhs = rhs;
    return true;
  }
  return false;
}

template <class T, class U>
inline bool chmax(T &lhs, const U &rhs) {
  if (lhs < rhs) {
    lhs = rhs;
    return true;
  }
  return false;
}

// [l, r) from l to r
struct range {
  struct itr {
    int i;
    constexpr itr(int i_): i(i_) { }
    constexpr void operator ++ () { ++i; }
    constexpr int operator * () const { return i; }
    constexpr bool operator != (itr x) const { return i != x.i; }
  };
  const itr l, r;
  constexpr range(int l_, int r_): l(l_), r(std::max(l_, r_)) { }
  constexpr itr begin() const { return l; }
  constexpr itr end() const { return r; }
};

// [l, r) from r to l
struct revrange {
  struct itr {
    int i;
    constexpr itr(int i_): i(i_) { }
    constexpr void operator ++ () { --i; }
    constexpr int operator * () const { return i; }
    constexpr bool operator != (itr x) const { return i != x.i; }
  };
  const itr l, r;
  constexpr revrange(int l_, int r_): l(l_ - 1), r(std::max(l_, r_) - 1) { }
  constexpr itr begin() const { return r; }
  constexpr itr end() const { return l; }
};

template <class T>
class modulo_int {
public:
  static constexpr int mod = T::value;
  static_assert(mod > 0, "mod must be positive");
private:
  long long value;
  constexpr void normalize() {
    value %= mod;
    if (value < 0) value += mod;
  }
public:
  constexpr modulo_int(long long value_ = 0): value(value_) { normalize(); }
  constexpr modulo_int operator - () const { return modulo_int(mod - value); }
  constexpr modulo_int operator ~ () const { return power(mod - 2); }
  constexpr long long operator () () const { return value; }
  constexpr modulo_int operator + (const modulo_int &rhs) const { return modulo_int(*this) += rhs; }
  constexpr modulo_int &operator += (const modulo_int &rhs) {
    if ((value += rhs.value) >= mod) value -= mod;
    return (*this);
  }
  constexpr modulo_int operator - (const modulo_int &rhs) const { return modulo_int(*this) -= rhs; }
  constexpr modulo_int &operator -= (const modulo_int &rhs) {
    if ((value += mod - rhs.value) >= mod) value -= mod;
    return (*this);
  }
  constexpr modulo_int operator * (const modulo_int &rhs) const { return modulo_int(*this) *= rhs; }
  constexpr modulo_int &operator *= (const modulo_int &rhs) {
    (value *= rhs.value) %= mod;
    return (*this);
  }
  constexpr modulo_int operator / (const modulo_int &rhs) const { return modulo_int(*this) /= rhs; }
  constexpr modulo_int &operator /= (const modulo_int &rhs) {
    return (*this) *= ~rhs;
  }
  constexpr bool operator == (const modulo_int &rhs) const {
    return value == rhs();
  }
  constexpr bool operator != (const modulo_int &rhs) const {
    return value != rhs();
  }
  constexpr modulo_int power (uint64_t exp) const {
    modulo_int result(1), mult(*this);
    while (exp > 0) {
      if (exp & 1) result *= mult;
      mult *= mult;
      exp >>= 1;
    }
    return result;
  }
  friend std::istream &operator >> (std::istream &stream, modulo_int &lhs) {
    stream >> lhs.value;
    lhs.normalize();
    return stream;
  }
  friend std::ostream &operator << (std::ostream &stream, const modulo_int &rhs) {
    return stream << rhs.value;
  }
};

using modint = modulo_int<std::integral_constant<int, 1000000007>>;
constexpr int mx = 1000;

int main() {
  int N, M;
  std::cin >> N >> M;
  std::vector<int> V(N), R(M);
  for (int &x: V) {
    std::cin >> x;
  }
  for (int &x: R) {
    std::cin >> x;
  }
  int A, B;
  std::cin >> A >> B;
  std::vector<modint> vdp(N * mx + 1);
  vdp.front() = 1;
  for (int i: range(0, N)) {
    for (int j: revrange(0, vdp.size())) {
      if (j - V[i] >= 0) {
        vdp[j] += vdp[j - V[i]];
      }
    }
  }
  std::vector<modint> rdp(M * mx + 1);
  rdp.front() = 1;
  for (int i: range(0, M)) {
    for (int j: revrange(0, rdp.size())) {
      if (j - R[i] >= 0) {
        rdp[j] += rdp[j - R[i]];
      }
    }
  }
  std::vector<modint> sum(vdp.size() + 1);
  for (int i: range(0, vdp.size())) {
    sum[i + 1] += sum[i] + vdp[i];
  }
  modint ans;
  for (int i: range(0, rdp.size())) {
    long long ub = std::min((long long) B * i + 1, (long long) vdp.size());
    long long lb = std::min((long long) A * i, (long long) vdp.size());
    assert(0 <= ub && ub <= vdp.size());
    assert(0 <= lb && lb <= vdp.size());
    ans += (sum[ub] - sum[lb]) * rdp[i];
  }
  std::cout << ans - 1 << '\n';
  return 0;
}