#include <bits/stdc++.h>
using namespace std;
#define int long long
#define INF (int)1e18
#define f first
#define s second
mt19937_64 RNG(chrono::steady_clock::now().time_since_epoch().count());
int n, m;
int a[101];
int w[2001];
int ass[2001];
void Solve()
{
cin >> n >> m;
int ans = 0;
set <int> av;
for (int i = 1; i <= n; i++){
av.insert(i);
cin >> a[i];
}
for (int i = 1; i <= m; i++) cin >> w[i];
queue <int> q;
for (int i = 1; i <= 2 * m; i++){
int x; cin >> x;
if (x > 0){
if (av.size()){
int u = *av.begin();
ans += a[u] * w[x];
ass[x] = u;
av.erase(u);
} else {
q.push(x);
}
} else {
x = -x;
if (q.size()){
int y = q.front();
int u = ass[x];
ass[y] = u;
ans += a[u] * w[y];
q.pop();
} else {
av.insert(ass[x]);
}
}
}
cout << ans << "\n";
}
int32_t main()
{
auto begin = std::chrono::high_resolution_clock::now();
ios_base::sync_with_stdio(0);
cin.tie(0);
int t = 1;
// cin >> t;
for(int i = 1; i <= t; i++)
{
//cout << "Case #" << i << ": ";
Solve();
}
auto end = std::chrono::high_resolution_clock::now();
auto elapsed = std::chrono::duration_cast<std::chrono::nanoseconds>(end - begin);
cerr << "Time measured: " << elapsed.count() * 1e-9 << " seconds.\n";
return 0;
}
