#include <bits/stdc++.h>
#define GET_MACRO(a, b, c, NAME, ...) NAME
#define rep(...) GET_MACRO(__VA_ARGS__, rep3, rep2)(__VA_ARGS__)
#define rep2(i, a) rep3 (i, 0, a)
#define rep3(i, a, b) for (int i = (a); i < (b); i++)
#define repr(...) GET_MACRO(__VA_ARGS__, repr3, repr2)(__VA_ARGS__)
#define repr2(i, a) repr3 (i, 0, a)
#define repr3(i, a, b) for (int i = (b) - 1; i >= (a); i--)
#define chmin(a, b) ((b) < a && (a = (b), true))
#define chmax(a, b) (a < (b) && (a = (b), true))
using namespace std;
typedef long long ll;

const ll inf = 1e18;
const ll MX = 101010;
ll N, M;
ll A[500], K[500];
ll dp[505][MX];

ll solve(ll D) {
	rep (i, 505) rep (j, MX) dp[i][j] = inf;
	dp[0][0] = 0;
	rep (i, N) {
		rep (j, MX) {
			chmin(dp[i + 1][j], dp[i][j]);
			if (j - A[i] >= 0) {
				chmin(dp[i + 1][j], dp[i + 1][j - A[i]] + 1);
			}
		}
	}
	if (D < MX) {
		return dp[N][D];
	} else {
		ll mx = *max_element(A, A + N);
		ll num = (D - MX) / mx;
		D -= num * mx;
		return dp[N][D] + num;
	}
}

int main() {
	cin >> N >> M;
	rep (i, N) cin >> A[i];
	rep (i, N) cin >> K[i];
	ll mx = 0;
	rep (i, N) mx += A[i] * K[i];
	ll mn = 0;
	repr (i, N) if (K[i] != 0) mn = A[i];
	ll D = mx - M;
	if (D < 0) {
		cout << -1 << endl;	
	} else {
		ll ans = solve(D);
		if (ans >= inf) {
			cout << -1 << endl;
		} else {
			cout << ans << endl;
		}
	}
	return 0;
}