/* -*- coding: utf-8 -*-
 *
 * 288.cc: No.288 貯金箱の仕事 - yukicoder
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>
 
using namespace std;

/* constant */

const int MAX_N = 500;
const int MAX_A = 500;

typedef long long ll;

const int INF = 1 << 30;
const ll LINF = 1LL << 60;

/* typedef */

typedef vector<int> vi;
typedef queue<int> qi;
typedef pair<int,int> pii;

/* global variables */

int as[MAX_N];
ll ks[MAX_N], dp[MAX_A * MAX_A + 1];

/* subroutines */

/* main */

int main() {
  int n;
  ll m;
  cin >> n >> m;

  for (int i = 0; i < n; i++) cin >> as[i];
  for (int i = 0; i < n; i++) cin >> ks[i];

  ll aksum = 0;
  for (int i = 0; i < n; i++) aksum += ks[i] * as[i];
  aksum -= m;

  if (aksum < 0) {
    puts("-1");
    return 0;
  }

  int maxa = as[n - 1], maxa2 = maxa * maxa;
  dp[0] = 0;

  for (int i = 1; i <= maxa2; i++) {
    ll mind = LINF;
    for (int j = 0; j < n; j++) {
      int &aj = as[j];
      if (i >= aj) {
	ll d = dp[i - aj] + 1;
	if (mind > d) mind = d;
      }
    }
    dp[i] = mind;
  }

  ll mind = LINF;
  int k = aksum % maxa;

  while (k <= aksum && k <= maxa2) {
    ll d = dp[k] + (aksum - k) / maxa;
    if (mind > d) mind = d;
    k += maxa;
  }

  printf("%lld\n", (mind >= LINF) ? -1 : mind);
  return 0;
}