#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <iomanip>
#include <cmath>
#include <stdio.h>
#include <queue>
#include <deque>
#include <cstdio>
#include <set>
#include <map>
#include <bitset>
#include <stack>
#include <cctype>
using namespace std;
long long v[110000] = {}, r[110000] = {};
long long const mod = 1000000007;
long long const mx = 100010;
int main() {
	long long n, m, a, b;
	cin >> n >> m;
	v[0] = 1, r[0] = 1;
	for (int i = 0; i < n; i++) {
		int vi;
		cin >> vi;
		for (int j = mx; j >= vi; j--) {
			v[j] += v[j - vi];
			v[j] %= mod;
		}
	}
	for (int i = 0; i < m; i++) {
		int ri;
		cin >> ri;
		for (int j = mx; j >= ri; j--) {
			r[j] += r[j - ri];
			r[j] %= mod;
		}
	}
	cin >> a >> b;
	long long ans = 0;
	for (int i = 1; i < mx; i++) {
		v[i] += v[i - 1];
		v[i] %= mod;
	}
	for (int i = 1; i < mx; i++) {
		ans += r[i] * (v[min(i * b, mx)] - v[min(i * a - 1, mx)]) % mod;
		ans %= mod;
	}
	cout << (ans + mod) % mod << endl;
}