#include <bits/stdc++.h>
#define int long long
using namespace std;
void solve() {
int n, m;
cin >> n >> m;
vector <int> r(n + 1);
for (int i = 1; i <= n; i++) {
cin >> r[i];
}
vector <int> v(m + 1);
for (int i = 1; i <= m; i++) {
cin >> v[i];
}
int ans = 0, num = n;
vector <int> free(n + 1,0);
queue <int> q;
for (int i = 0; i < m * 2; i++) {
int x;
cin >> x;
if (x > 0) {
if (num) {
for (int j = 1; j <= n; j++) {
if (free[j] == 0) {
free[j] = x;
ans += (v[x] * r[j]);
break;
}
}
}
else {
q.push(x);
}
}
else {
for (int j = 1; j <= n; j++) {
if (free[j] == abs(x)) {
free[j] = 0;
if (!q.empty()) {
free[j] = q.front();
q.pop();
ans += (v[free[j]] * r[j]);
}
break;
}
}
}
}
cout << ans << endl;
}
signed main() {
ios::sync_with_stdio(false);
cin.tie(0);
int t = 1;
//cin >> t;
while (t--) {
solve();
}
}
