// yuki 1043 直列大学 // 2021.8.12 #include #define gc() getchar_unlocked() #define pc(c) putchar_unlocked(c) int in() { // 非負整数の入力 int n = 0; int c = gc(); do n = 10 * n + (c & 0xf); while ((c = gc()) >= '0'); return n; } typedef long long ll; const int mod = 1e9+7; int V[105], vdp[100005]; int N; int R[105], rdp[100005]; int M; int s[100005]; void cal_dp(int *a, int w, int *dp, int ma) { int i, j; dp[0] = 1; for (i = 0; i < w; ++i) { for (j = ma; j >= 0; --j) if (dp[j]) dp[j+a[i]] += dp[j]; } } int main() { int A, B, i; ll ans; N = in(), M = in(); for (i = 0; i < N; ++i) V[i] = in(); cal_dp(V, N, vdp, N*1000); for (i = 0; i < M; ++i) R[i] = in(); cal_dp(R, M, rdp, M*1000); for (i = 1; i <= M*1000; ++i) s[i] = (s[i-1]+rdp[i]) % mod; /* for (i = 0; i <= 20; ++i) if (vdp[i]) printf("(%d,%d) ", i, vdp[i]); printf("\n"); for (i = 0; i <= 20; ++i) if (rdp[i]) printf("(%d,%d) ", i, rdp[i]); printf("\n"); for (i = 0; i <= 20; ++i) printf("%d ", s[i]); printf("\n"); */ A = in(), B = in(); ans = 0; for (i = 1; i <= N*1000; ++i) if (vdp[i]) { ans += (ll)vdp[i] * (s[i/A]-s[(i-1)/B]) % mod; } ans %= mod; if (ans < 0) ans += mod; printf("%d\n", (int)ans); return 0; }