#include <iostream>
#include <vector>
#include <cstdio>
#include <sstream>
#include <map>
#include <string>
#include <algorithm>
#include <queue>
#include <cmath>
#include <set>
using namespace std;

int main(){
	long long n,m;
	cin >> n >> m;
	vector<long long> a(n), k(n);

	for(int i=0; i<n; i++){
		cin >> a[i];
	}
	for(int i=0; i<n; i++){
		cin >> k[i];
	}

	long long sum = 0;
	for(int i=0; i<n; i++){
		sum += a[i] * k[i];
	}

	sum -= m;
	if(sum<0){
		cout << -1 << endl;

		return 0;
	}

	long long cnt = 0;

	long long sz = a[n-1]*a[n-1]+1;
	vector<long long> dp(sz, 1LL<<50);
	dp[0] = 0;
	for(int i=0; i<n; i++){
		for(long long v=a[i]; v<sz; v++){
			dp[v] = min(dp[v], dp[v-a[i]] + 1);
		}

	}

	auto check = [&](long long x){
		return a.back()*a.back() < sum - x*a.back();
	};

	long long lb = sum/(a.back()*a.back());
	lb *= a.back();

	/*
	long long ub = 1e13;
	while(ub-lb>1){
		long long mid = (lb+ub)/2;
		bool ok = check(mid);
		(ok? lb : ub) = mid;
	}
	*/

	cnt += lb;
	sum -= lb*a.back();

	cnt = dp[sum]!=(1LL<<50)?(cnt+dp[sum]):-1;

	cout << cnt << endl;

	return 0;
}