#include<bits/stdc++.h>

using namespace std;
typedef unsigned int uint;
typedef long long int ll;
typedef unsigned long long int ull;

#define debugv(v) printf("L%d %s => ",__LINE__,#v);for(auto e:v){cout<<e<<" ";}cout<<endl;
#define debugm(m) printf("L%d %s is..\n",__LINE__,#m);for(auto v:m){for(auto e:v){cout<<e<<" ";}cout<<endl;}
#define debuga(m,w) printf("L%d %s is => ",__LINE__,#m);for(int x=0;x<(w);x++){cout<<(m)[x]<<" ";}cout<<endl;
#define debugaa(m,w,h) printf("L%d %s is..\n",__LINE__,#m);for(int y=0;y<(h);y++){for(int x=0;x<(w);x++){cout<<(m)[x][y]<<" ";}cout<<endl;}
#define ALL(v) (v).begin(),(v).end()
#define BIGINT 0x7FFFFFFF
#define E107 1000000007

template<typename T1,typename T2>
ostream& operator <<(ostream &o,const pair<T1,T2> p){o<<"("<<p.first<<":"<<p.second<<")";return o;}

int tim,n;

int datac[20];
int datav[20];

int dp[11000];


int main(){
    int i,j,k,l,t;
    
    cin>>tim>>n;
    
    for (i=0;i<n;i++){
        scanf("%d",datac+i);
    }
    vector<int> manzok(n);
    for (i=0;i<n;i++){
        scanf("%d",datav+i);
    }
    int result=0;
    for (i=0;i<n;i++){
        for(;datav[i];datav[i]/=2)
            for (t=tim;0<=t;t--){
                dp[t+datac[i]]=max(dp[t+datac[i]],dp[t]+datav[i]);
            }
    }
    for (t=tim;0<=t;t--)
        result=max(dp[t],result);
    
    cout<<result<<endl;

    return 0;
}