#!/usr/bin/ python3.8
import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines

N, M = map(int, readline().split())
A = tuple(map(int, readline().split()))
K = tuple(map(int, readline().split()))

M = sum(a * k for a, k in zip(A, K)) - M
if M < 0:
    print(-1)
    exit()

U = 260000
INF = 10 ** 18
dp = [INF] * U
dp[0] = 0
for a in A:
    for i in range(a, U):
        x = dp[i - a] + 1
        if dp[i] > x:
            dp[i] = x

n = A[-1]
k = max(0, (M - U) // n + 1)
M -= k * n
if dp[M] > 10 ** 17:
    print(-1)
else:
    print(dp[M] + k)