#include<bits/stdc++.h>

int main(){
    using namespace std;
    constexpr unsigned long MOD = 1000000007;
    unsigned long N, M, Sv{1}, Sr{1};
    cin >> N >> M;
    vector<unsigned long> dp1{1}, dp2{1};
    dp1.reserve(50000);
    dp2.reserve(50000);
    for(unsigned long i{0}, V; i < N; ++i){
        cin >> V;
        dp1.resize(Sv += V);
        for(unsigned long j{Sv}; j-- > V; )(dp1[j] += dp1[j - V]) %= MOD;
    }
    for(unsigned long i{0}, R; i < M; ++i){
        cin >> R;
        dp2.resize(Sr += R);
        for(unsigned long j{Sr}; j-- > R; )(dp2[j] += dp2[j - R]) %= MOD;
    }
    partial_sum(dp1.rbegin(), dp1.rend(), dp1.rbegin());
    const auto& access = [&Sv, &dp1](long i) -> unsigned long {
        if(i < Sv)return dp1[i] %= MOD;
        return 0;
    };
    unsigned long A, B;
    cin >> A >> B;
    unsigned long ans{0};
    for(unsigned long i{1}; i < Sr; ++i)ans += dp2[i] * (access(A * i) + MOD - access(B * i + 1)) % MOD;
    cout << ans << endl;
    return 0;
}