#define _CRT_SECURE_NO_WARNINGS
#include "bits/stdc++.h"
#define rep(i,n) for(int i = 0;i < n;i++)
#define P(p) cout<<(p)<<endl;
using namespace std;
typedef long long ll;
int dx[] = { 0, 1, 0, -1 };
int dy[] = { -1, 0, 1, 0 };

int sttoi(std::string str) {
	int ret;
	std::stringstream ss; ss << str;
	ss >> ret;
	return ret;
}

ll gcd(ll a, ll b){
	if (b > a)swap(a, b); if (b == 0)return a; else{ return gcd(b, a%b); }
}

void solve() {
	int t, n, c[15],v[15];
	int dp[10500];
	rep(i, 10500)dp[i] = 0;
	cin >> t >> n;
	rep(i, n)cin >> c[i];
	rep(i, n)cin >> v[i];
	for (int i = 0; i < n ; i++){
		while (v[i] > 0){
			for (int j = t; j >= 0; j--){
				dp[j + c[i]] = max(dp[j + c[i]], dp[j] + v[i]);
			}
			v[i] /= 2;
		}
	}
	int maxi = -1;
	rep(i, t + 1){
		maxi = max(maxi, dp[i]);
	}
	P(maxi);
}

int main() {
	solve();
	return 0;
}