#include "bits/stdc++.h"
// Begin Header {{{
#define all(x) (x).begin(), (x).end()
#define rep(i, s, n) for (i64 i = (s), i##_limit = (n); i < i##_limit; ++i)
#define repr(i, s, t) for (i64 i = (s), i##_limit = (t); i >= i##_limit; --i)
#define repc(i, s, t) for (i64 i = (s), i##_limit = (t); i <= i##_limit; ++i)
#define var(type, ...) \
    type __VA_ARGS__;  \
    read(__VA_ARGS__);
#ifndef DBG
#define dump(...)
#endif
using namespace std;
using i64 = int_fast64_t;
using pii = pair<i64, i64>;
template <class T, class U>
inline bool chmax(T &a, const U &b) {
    return b > a && (a = b, true);
}
template <class T, class U>
inline bool chmin(T &a, const U &b) {
    return b < a && (a = b, true);
}
constexpr int INF = 0x3f3f3f3f;
constexpr i64 LINF = 0x3f3f3f3f3f3f3f3fLL;

template <class T>
inline vector<T> makeV(const T &initValue, size_t sz) {
    return vector<T>(sz, initValue);
}

template <class T, class... Args>
inline auto makeV(const T &initValue, size_t sz, Args... args) {
    return vector<decltype(makeV<T>(initValue, args...))>(
        sz, makeV<T>(initValue, args...));
}

template <class T>
inline istream &operator>>(istream &is, vector<T> &vec) {
    for (auto &e : vec) is >> e;
    return is;
}

inline void read() {}

template <class Head, class... Tail>
inline void read(Head &head, Tail &... tail) {
    cin >> head;
    read(tail...);
}

inline void print() { cout << "\n"; }

template <class Head, class... Tail>
inline void print(Head &&head, Tail &&... tail) {
    cout << head;
    if (sizeof...(tail)) cout << ' ';
    print(forward<Tail>(tail)...);
}

template <class T>
inline ostream &operator<<(ostream &os, const vector<T> &vec) {
    static constexpr const char *delim[] = {" ", ""};
    for (const auto &e : vec) os << e << delim[&e == &vec.back()];
    return os;
}

template <class Container>
struct Rev {
    Container &x_;
    inline Rev(Container &x) : x_(x) {}
    inline auto begin() { return rbegin(x_); }
    inline auto end() { return rend(x_); }
};
// }}} End Header

constexpr int MOD = int(1e9) + 7;

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    var(int, N, M);
    vector<i64> V(N), R(M);
    read(V, R);
    var(i64, A, B);

    constexpr int MX = 1e6 + 1000;

    vector<i64> dpV(MX + 2000);
    dpV[0] = 1;
    for (const i64 v : V) {
        repr(i, MX, 0)(dpV[i + v] += dpV[i]) %= MOD;
    }

    vector<i64> dpR(MX + 2000);
    dpR[0] = 1;
    for (const i64 r : R) {
        repr(i, MX, 0)(dpR[i + r] += dpR[i]) %= MOD;
    }

    vector<i64> cumV(MX + 1);
    rep(i, 0, MX) { cumV[i + 1] = (cumV[i] + dpV[i]) % MOD; }

    i64 ans = 0;
    repc(sumR, 1, 1e6) {
        if (dpR[sumR] == 0) continue;
        if (A * sumR >= MX || B * sumR >= MX) continue;
        const i64 vv = (cumV[B * sumR + 1] - cumV[A * sumR] + MOD) % MOD;
        ans += dpR[sumR] * vv % MOD;
        ans %= MOD;
    }

    print(ans);

    return 0;
}