#include #include #include #include #include #include #include #include #include #include #include #include using namespace std; #define rep(i, n) for(int(i) = 0; (i) < (n); (i)++) #define FOR(i, m, n) for(int(i) = (m); (i) < (n); (i)++) #define All(v) (v).begin(), (v).end() #define pb push_back #define MP(a, b) make_pair((a), (b)) template vector make_vec(size_t a, T val) { return vector(a, val); } template auto make_vec(size_t a, Ts... ts) { return vector(ts...))>(a, make_vec(ts...)); } using ll = long long; using pii = pair; using pll = pair; const int INF = 1 << 30; const ll LINF = 1LL << 60; const int MOD = 1e9 + 7; template class ModInt { using u64 = uint_fast64_t; public: u64 val; ModInt(const u64 x = 0) : val((x + MOD) % MOD) {} constexpr u64 &value() { return val; } constexpr ModInt operator-() { return val ? MOD - val : 0; } constexpr ModInt operator+(const ModInt &rhs) const { return ModInt(*this) += rhs; } constexpr ModInt operator-(const ModInt &rhs) const { return ModInt(*this) -= rhs; } constexpr ModInt operator*(const ModInt &rhs) const { return ModInt(*this) *= rhs; } constexpr ModInt operator/(const ModInt &rhs) const { return ModInt(*this) /= rhs; } constexpr ModInt &operator+=(const ModInt &rhs) { val += rhs.val; if(val >= MOD) { val -= MOD; } return *this; } constexpr ModInt &operator-=(const ModInt &rhs) { if(val < rhs.val) { val += MOD; } val -= rhs.val; return *this; } constexpr ModInt &operator*=(const ModInt &rhs) { val = val * rhs.val % MOD; return *this; } constexpr ModInt &operator/=(const ModInt &rhs) { *this *= rhs.inv(); return *this; } constexpr bool operator==(const ModInt &rhs) { return this->a == rhs.a; } constexpr bool operator!=(const ModInt &rhs) { return this->a != rhs.a; } friend constexpr ostream &operator<<(ostream &os, const ModInt &x) { return os << x.val; } friend constexpr istream &operator>>(istream &is, ModInt &x) { return is >> x.val; } constexpr ModInt inv() const { return ModInt(*this).pow(MOD - 2); } constexpr ModInt pow(ll e) const { u64 x = 1, p = val; while(e > 0) { if(e % 2 == 0) { p = (p * p) % MOD; e /= 2; } else { x = (x * p) % MOD; e--; } } return ModInt(x); } }; using mint = ModInt; int main() { int N, M; cin >> N >> M; vector V(N), R(M); rep(i, N) cin >> V[i]; rep(i, M) cin >> R[i]; ll A, B; cin >> A >> B; auto vdp = make_vec(100001, 0), rdp = make_vec(100001, 0); vdp[0] = 1, rdp[0] = 1; for(int i = 0; i < N; i++) { auto next = make_vec(100001, 0); for(int j = 0; j < 100001; j++) { if(vdp[j]) { next[j] += vdp[j]; next[j + V[i]] += vdp[j]; } } swap(vdp, next); } for(int i = 0; i < M; i++) { auto next = make_vec(100001, 0); for(int j = 0; j < 100001; j++) { if(rdp[j]) { next[j] += rdp[j]; next[j + R[i]] += rdp[j]; } } swap(rdp, next); } auto vsum = make_vec(100002, mint(0)); rep(i, 100001) { vsum[i + 1] = vsum[i] + vdp[i]; } mint res = 0; for(int i = 1; i <= 100000; i++) { if(rdp[i]) { res += (vsum[i * B + 1] - vsum[i * A]) * rdp[i]; } } cout << res << endl; return 0; }