#include <bits/stdc++.h>
using namespace std;
int n,m,r[101],w[2001],p[2001],res,x;
queue <int> q;
priority_queue <int, vector <int>, greater <int>> pq;
void park(int i){
if (pq.empty()){
q.push(i);
return;
}
res+=r[pq.top()]*w[i];
p[i]=pq.top();
pq.pop();
}
int main(){
ios_base::sync_with_stdio(NULL);cin.tie(nullptr);
cin >> n >> m;
for (int i=1;i<=n;i++){
cin >> r[i];
pq.push(i);
}
for (int i=1;i<=m;i++)
cin >> w[i];
for (int i=1;i<=m*2;i++){
cin >> x;
if (x>0){
park(x);
continue;
}
pq.push(p[-x]);
if (!q.empty()){
park(q.front());
q.pop();
}
}
cout << res;
}
