include<bits/stdc++.h>

using namespace std;

long long read(){

char c=getchar();
long long num=0;long long f=1;
while(c<'0'||c>'9'){if(c=='-')f=-1;c=getchar();}
while(c>='0'&&c<='9'){num=num*10+(c-'0');c=getchar();}
return num*f;

}

void qwq(long long x){

if(x>9)qwq(x/10);
putchar(x%10+'0');

}

void write(long long x){

if(x<0){x=-x;putchar('-');}
qwq(x);putchar('\n');

}

struct wzy{

long long ai,bi,ci;

}container[60];

long long dp[100010];

bool cmp(wzy a,wzy b){

return (a.bi*a.ci)<(b.bi*b.ci);

}

int main(){

long long T=read();long long N=read();
for(long long i=1;i<=N;i++)container[i].ai=read();
for(long long i=1;i<=N;i++)container[i].bi=read();
for(long long i=1;i<=N;i++)container[i].ci=read();
sort(container+1,container+N+1,cmp);

for(long long i=1;i<=N;i++){
    for(long long j=T;j>=container[i].ci;j--){
        dp[j]=max(dp[j],dp[j-container[i].ci]+(container[i].ai-j*container[i].bi));
    }
}

long long ans=0;
for(long long i=1;i<=T;i++)ans=max(ans,dp[i]);
write(ans);
return 0;

}