#include <bits/stdc++.h>
using namespace std;
int main() {
int n, m;
cin >> n >> m;
vector <int> rate(n);
for (int i = 0; i < n; i++)
cin >> rate[i];
vector <int> wt(m+1);
multiset <int> available;
for (int i = 1; i <= m; i++)
cin >> wt[i];
for (int i = 0; i < n; i++)
available.insert(i);
vector <int> occ(m+1);
queue <int> q;
int ans = 0;
for (int i = 0; i < 2 * m; i++) {
int x;
cin >> x;
if (x > 0) {
if (available.empty())
q.push(x);
else {
occ[x] = *available.begin();
available.erase(available.begin());
ans += wt[x] * rate[occ[x]];
}
} else {
x = -x;
if (!q.empty()) {
ans += rate[occ[x]] * wt[q.front()];
occ[q.front()] = occ[x];
q.pop();
} else {
available.insert(occ[x]);
}
}
}
cout << ans << '\n';
}
