import algorithm, math, sequtils, strutils let read* = iterator: string = while true: (for s in stdin.readLine.split: yield s) template input*(T: static[typedesc]): untyped = when T is int: read().parseInt elif T is float: read().parseFloat elif T is string: read() # -------------------------------------------------- # template useModInt*(p: static[Positive]) = type ModInt* {.inject.} = distinct int proc toModInt*(n: int): ModInt {.inline.} = if n >= p + p: ModInt(n mod p) elif n >= p: ModInt(n - p) elif n >= 0: ModInt(n) elif n >= -p: ModInt(n + p) else: ModInt((n mod p + p) mod p) proc inverse*(n: range[1 .. p - 1]): ModInt {.inline.} = var (sx, tx, s, t) = (0, 1, p, n) while t != 1: let k = s div t s -= t * k; swap(s, t) sx -= tx * k; swap(sx, tx) return toModInt(tx) proc inverse*(n: ModInt): ModInt {.inline.} = inverse(int(n)) proc `$`*(n: ModInt): string {.borrow.} proc `+`*(n: ModInt): ModInt {.borrow.} proc `-`*(n: ModInt): ModInt {.inline.} = ModInt((p - int(n)) * int(int(n) != 0)) proc `<`*(n: ModInt, m: ModInt): bool {.borrow.} proc `<`*(n: ModInt, m: int): bool {.borrow.} proc `<`*(n: int, m: ModInt): bool {.borrow.} proc `<=`*(n: ModInt, m: ModInt): bool {.borrow.} proc `<=`*(n: ModInt, m: int): bool {.borrow.} proc `<=`*(n: int, m: ModInt): bool {.borrow.} proc `==`*(n: ModInt, m: ModInt): bool {.borrow.} proc `==`*(n: ModInt, m: int): bool {.borrow.} proc `==`*(n: int, m: ModInt): bool {.borrow.} proc `+`*(n: ModInt, m: ModInt): ModInt {.inline.} = ModInt(int(n) + int(m) - p * int(int(n) + int(m) >= p)) proc `+`*(n: ModInt, m: int): ModInt {.inline.} = toModInt(int(n) + m) proc `+`*(n: int, m: ModInt): ModInt {.inline.} = toModInt(n + int(m)) proc `-`*(n: ModInt, m: ModInt): ModInt {.inline.} = ModInt(int(n) - int(m) + p * int(int(n) - int(m) < 0)) proc `-`*(n: ModInt, m: int): ModInt {.inline.} = toModInt(int(n) + m) proc `-`*(n: int, m: ModInt): ModInt {.inline.} = toModInt(n + int(m)) proc `*`*(n: ModInt, m: ModInt): ModInt {.inline.} = toModInt(int(n) * int(m)) proc `*`*(n: ModInt, m: int): ModInt {.inline.} = toModInt(int(n) * m) proc `*`*(n: int, m: ModInt): ModInt {.inline.} = toModInt(n * int(m)) proc `/`*(n: ModInt, m: ModInt): ModInt {.inline.} = toModInt(int(n) * int(inverse(m))) proc `/`*(n: ModInt, m: int): ModInt {.inline.} = toModInt(int(n) * int(inverse(m))) proc `/`*(n: int, m: ModInt): ModInt {.inline.} = toModInt(n * int(inverse(m))) proc `+=`*(n: var ModInt, m: ModInt) {.inline.} = n = n + m proc `+=`*(n: var ModInt, m: int) {.inline.} = n = n + m proc `-=`*(n: var ModInt, m: ModInt) {.inline.} = n = n - m proc `-=`*(n: var ModInt, m: int) {.inline.} = n = n - m proc `*=`*(n: var ModInt, m: ModInt) {.inline.} = n = n * m proc `*=`*(n: var ModInt, m: int) {.inline.} = n = n * m proc `/=`*(n: var ModInt, m: ModInt) {.inline.} = n = n / m proc `/=`*(n: var ModInt, m: int) {.inline.} = n = n / m # -------------------------------------------------- # useModInt(1000000007) let N, M = input(int) let V = @[0] & newSeqWith(N, input(int)) let R = @[0] & newSeqWith(M, input(int)) let A, B = input(int) proc f(N: int, V: seq[int]): seq[ModInt] = var dp: array[0 .. 100, array[0 .. 100000, ModInt]] dp[0][0] = ModInt(1) for i in 1 .. N: for j in 0 .. 100000: if j - V[i] >= 0: dp[i][j] += dp[i - 1][j - V[i]] dp[i][j] += dp[i - 1][j] var A = newSeq[ModInt](100001) for i in 1 .. 100000: A[i] = dp[N][i] return A let P = f(N, V).cumsummed let Q = f(M, R) var res = ModInt(0) for j in 0 .. 100000: let R = (j * B).clamp(0, 100000) let L = (j * A - 1).clamp(0, 100000) res += (P[R] - P[L]) * Q[j] echo res