#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
#include <sstream>
#include <cstring>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <queue>
#include <stack>
#include <map>
#include <set>
#include <numeric>
#include <cctype>
#include <tuple>
#include <array>
#include <climits>
#include <bitset>
#include <cassert>

#ifdef _MSC_VER
#include <agents.h>
#endif

#define FOR(i, a, b) for(int i = (a); i < (int)(b); ++i)
#define rep(i, n) FOR(i, 0, n)
#define ALL(v) v.begin(), v.end()
#define REV(v) v.rbegin(), v.rend()
#define MEMSET(v, s) memset(v, s, sizeof(v))
#define UNIQUE(v) (v).erase(unique(ALL(v)), (v).end())
#define MP make_pair
#define MT make_tuple

using namespace std;

typedef long long ll;
typedef long double ld;
typedef pair<int, int> P;

int main(){
	cin.tie(0);
	ios::sync_with_stdio(false);
	cout.setf(ios::fixed);
	cout.precision(20);

	int t, n;
	cin >> t >> n;

	vector<int> w(n), v(n);
	rep(i, n) cin >> w[i];
	rep(i, n) cin >> v[i];
	rep(i, w.size()){
		if (v[i] / 2){
			w.push_back(w[i]);
			v.push_back(v[i] / 2);
		}
	}

	vector<int> dp(t + 1);
	for (int i = 0; i < w.size(); ++i){
		for (int j = t - w[i]; j >= 0; --j){
			dp[j + w[i]] = max(dp[j + w[i]], dp[j] + v[i]);
		}
	}
	cout << dp[t] << endl;
}