#include <bits/stdc++.h>
using namespace std;
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
int n, m;
cin >> n >> m;
vector<int> a(n), b(m + 1);
for (int i = 0; i < n; i++) {
cin >> a[i];
}
for (int i = 1; i <= m; i++) {
cin >> b[i];
}
vector<bool> is(n);
vector<int> id(m + 1);
queue<int> q;
int ans = 0;
for (int i = 0; i < 2 * m; i++) {
int x;
cin >> x;
if (x > 0) {
bool can = 0;
for (int j = 0; j < n; j++) {
if (!is[j]) {
can = 1;
is[j] = 1;
id[x] = j;
ans += b[x] * a[j];
break;
}
}
if (!can) {
q.push(x);
}
}
else {
x = -x;
is[id[x]] = 0;
id[x] = 0;
if (q.empty()) continue;
int y = q.front(); q.pop();
for (int j = 0; j < n; j++) {
if (!is[j]) {
is[j] = 1;
id[y] = j;
ans += b[y] * a[j];
break;
}
}
}
}
cout << ans << '\n';
return 0;
}
