#include <bits/stdc++.h>
using namespace std;
constexpr int INF = 1e9;
int main() {
int n, m;
cin >> n >> m;
vector<int> rates(n);
for (int &r : rates) {
cin >> r;
}
vector<int> weights(m);
for (int &w : weights) {
cin >> w;
}
vector<int> arrivals(m * 2);
for (int &a : arrivals) {
cin >> a;
}
set<int> garage;
for (int i = 0; i < n; i++) garage.insert(i);
vector<int> spaceUsed(m, -INF);
int ans = 0;
queue<int> q;
for (int car : arrivals) {
if (car < 1) {
int g = spaceUsed[abs(car) - 1];
garage.insert(g);
}
else {
q.push(car - 1);
}
while (garage.size() && q.size()) {
int g = *garage.begin(); garage.erase(garage.begin());
int curr = q.front(); q.pop();
ans += weights[curr] * rates[g];
spaceUsed[curr] = g;
}
}
printf("%d\n", ans);
}
