import std.conv, std.functional, std.range, std.stdio, std.string; import std.algorithm, std.array, std.bigint, std.bitmanip, std.complex, std.container, std.math, std.mathspecial, std.numeric, std.regex, std.typecons; import core.bitop; class EOFException : Throwable { this() { super("EOF"); } } string[] tokens; string readToken() { for (; tokens.empty; ) { if (stdin.eof) { throw new EOFException; } tokens = readln.split; } auto token = tokens.front; tokens.popFront; return token; } int readInt() { return readToken.to!int; } long readLong() { return readToken.to!long; } real readReal() { return readToken.to!real; } bool chmin(T)(ref T t, in T f) { if (t > f) { t = f; return true; } else { return false; } } bool chmax(T)(ref T t, in T f) { if (t < f) { t = f; return true; } else { return false; } } int binarySearch(alias pred, T)(in T[] as) { int lo = -1, hi = cast(int)(as.length); for (; lo + 1 < hi; ) { const mid = (lo + hi) >> 1; (unaryFun!pred(as[mid]) ? hi : lo) = mid; } return hi; } int lowerBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a >= val)); } int upperBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a > val)); } struct ModInt(int M_) { import std.conv : to; alias M = M_; int x; this(ModInt a) { x = a.x; } this(long a) { x = cast(int)(a % M); if (x < 0) x += M; } ref ModInt opAssign(long a) { return (this = ModInt(a)); } ref ModInt opOpAssign(string op)(ModInt a) { static if (op == "+") { x += a.x; if (x >= M) x -= M; } else static if (op == "-") { x -= a.x; if (x < 0) x += M; } else static if (op == "*") { x = cast(int)((cast(long)(x) * a.x) % M); } else static if (op == "/") { this *= a.inv(); } else static assert(false); return this; } ref ModInt opOpAssign(string op)(long a) { static if (op == "^^") { if (a < 0) return (this = inv()^^(-a)); ModInt t2 = this, te = ModInt(1); for (long e = a; e > 0; e >>= 1) { if (e & 1) te *= t2; t2 *= t2; } x = cast(int)(te.x); return this; } else return mixin("this " ~ op ~ "= ModInt(a)"); } ModInt inv() const { int a = x, b = M, y = 1, z = 0, t; for (; ; ) { t = a / b; a -= t * b; if (a == 0) { assert(b == 1 || b == -1); return ModInt(b * z); } y -= t * z; t = b / a; b -= t * a; if (b == 0) { assert(a == 1 || a == -1); return ModInt(a * y); } z -= t * y; } } ModInt opUnary(string op: "-")() const { return ModInt(-x); } ModInt opBinary(string op, T)(T a) const { return mixin("ModInt(this) " ~ op ~ "= a"); } ModInt opBinaryRight(string op)(long a) const { return mixin("ModInt(a) " ~ op ~ "= this"); } bool opCast(T: bool)() const { return (x != 0); } string toString() const { return x.to!string; } } enum MO = 1000000007; alias Mint = ModInt!MO; Mint[] doIt(int[] as) { const asSum = as.sum; auto dp = new Mint[asSum + 1]; dp[0] = 1; foreach (a; as) { foreach_reverse (x; a .. asSum + 1) { dp[x] += dp[x - a]; } } return dp; } void main() { try { for (; ; ) { const N = readInt(); const M = readInt(); auto V = new int[N]; foreach (i; 0 .. N) { V[i] = readInt(); } auto R = new int[M]; foreach (j; 0 .. M) { R[j] = readInt(); } const A = readLong(); const B = readLong(); const dpV = doIt(V); const dpR = doIt(R); debug { writeln("dpV = ", dpV); writeln("dpR = ", dpR); } const dpVLen = cast(int)(dpV.length); const dpRLen = cast(int)(dpR.length); auto dpVSum = new Mint[dpVLen + 1]; foreach (x; 0 .. dpVLen) { dpVSum[x + 1] = dpVSum[x] + dpV[x]; } Mint ans; foreach (y; 1 .. dpRLen) { // A <= x / y <= B const lb = max(A * y, 0); const ub = min(B * y + 1, dpVLen); if (lb <= ub) { ans += (dpVSum[cast(int)(ub)] - dpVSum[cast(int)(lb)]) * dpR[y]; } } writeln(ans); } } catch (EOFException e) { } }