#include <iostream>
#include <string>
#include <utility>
#include <algorithm>
#include <map>
#include <set>
#include <vector>
#include <cmath>
#include <cstdlib>
#include <queue>
#include <stack>
#include <iomanip>
#include <fstream>
#include <unordered_map>
#include <unordered_set>
#include <assert.h>
using namespace std;


#define REP(i, n) for(ll i = 0;i < n;i++)
#define REPR(i, n) for(ll i = n;i >= 0;i--)
#define FOR(i, m, n) for(ll i = m;i < n;i++)
#define FORR(i, m, n) for(ll i = m;i >= n;i--)
#define REPO(i, n) for(ll i = 1;i <= n;i++)
#define ll long long
#define INF (ll)1 << 60
#define MINF (2 * INF)
#define ALL(n) n.begin(),n.end()
#define MOD 1000000007
#define P pair<ll, ll>

ll dp[1100000], dp2[1100000], l, r;
int main() {
	ll n, m;
	cin >> n >> m;
	dp[0] = 1;
	dp2[0] = 1;
	vector<ll> a(n), b(m);
	REP(i, n)cin >> a[i];
	REP(i, m)cin >> b[i];
	cin >> l >> r;
	REP(i, n) REPR(j, 1000100) { dp[j + a[i]] += dp[j]; dp[j + a[i]] %= MOD; }
	REP(i, m) REPR(j, 1000100) { dp2[j + b[i]] += dp2[j]; dp2[j + b[i]] %= MOD; }
	REP(i, 1000100) {
		dp[i + 1] += dp[i];
		dp[i + 1] %= MOD;
	}
	ll ans = 0;
	REPO(i, 1000000) {
		ans += (dp[min(r * i, 1000000ll)] - dp[min(l * i - 1, 1000000ll)] + MOD * 2) % MOD * dp2[i] % MOD;
		ans %= MOD;
	}
	cout << ans << endl;
}