/* -*- coding: utf-8 -*-
 *
 * 1043.cc:  No.1043 直列大学 - yukicoder
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>
 
using namespace std;

/* constant */

const int MAX_N = 100;
const int MAX_M = 100;
const int MAX_V = 1000;
const int MAX_R = 1000;
const int MAX_VS = MAX_V * MAX_N;
const int MAX_RS = MAX_R * MAX_M;
const int MOD = 1000000007;

/* typedef */

typedef long long ll;

/* global variables */

int vs[MAX_N], rs[MAX_M];
int vdp[MAX_VS + 1], rdp[MAX_RS + 1];

/* subroutines */

inline void addmod(int &a, int b) { a = (a + b) % MOD; }

/* main */

int main() {
  int n, m;
  scanf("%d%d", &n, &m);

  for (int i = 0; i < n; i++) scanf("%d", vs + i);
  for (int i = 0; i < m; i++) scanf("%d", rs + i);

  int a, b;
  scanf("%d%d", &a, &b);

  int vsum = 0;
  vdp[0] = 1;
  for (int i = 0; i < n; i++) {
    for (int j = vsum; j >= 0; j--) addmod(vdp[j + vs[i]], vdp[j]);
    vsum += vs[i];
  }
  for (int j = 0; j < vsum; j++) addmod(vdp[j + 1], vdp[j]);
  
  int rsum = 0;
  rdp[0] = 1;
  for (int i = 0; i < m; i++) {
    for (int j = rsum; j >= 0; j--) addmod(rdp[j + rs[i]], rdp[j]);
    rsum += rs[i];
  }
  //for (int j = 0; j < rsum; j++) addmod(rdp[j + 1], rdp[j]);

  int sum = 0;
  for (int i = 1; i <= rsum && (ll)a * i <= vsum; i++)
    if (rdp[i] > 0) {
      int j0 = a * i - 1;
      int j1 = min((ll)b * i, (ll)vsum);
      sum = (sum + (ll)rdp[i] * ((vdp[j1] + MOD - vdp[j0]) % MOD) % MOD) % MOD;
    }

  printf("%d\n", sum);
  return 0;
}