#include <bits/stdc++.h>
using namespace std;
const int nx=2e3+5;
int n, m, w[nx], s[nx], x, l[nx], res;
priority_queue<int, vector<int>, greater<int>> pq;
queue<int> q;
int main()
{
cin.tie(NULL)->sync_with_stdio(false);
cin>>n>>m;
for (int i=1; i<=n; i++) cin>>s[i], pq.push(i);
for (int i=1; i<=m; i++) cin>>w[i];
for (int i=1; i<=2*m; i++)
{
cin>>x;
if (x<0) pq.push(l[-x]);
else
{
if (!pq.empty())
{
l[x]=pq.top();
pq.pop();
res+=s[l[x]]*w[x];
}
else q.push(x);
}
while (!pq.empty()&&!q.empty())
{
auto t=pq.top();
pq.pop();
res+=s[t]*w[q.front()];
l[q.front()]=t;
q.pop();
}
}
cout<<res;
}
