#include <bits/stdc++.h>
using namespace std;
int main () {
long long parkingSpace, cars;
vector<long long> parkingStateArr;
vector<long long> parkingPriceArr;
vector<long long> carArr;
cin >> parkingSpace >> cars;
while (parkingSpace--) {
long long price;
cin >> price;
parkingPriceArr.push_back(price);
parkingStateArr.push_back(-1);
}
while (cars--) {
long long carWeight;
cin >> carWeight;
carArr.push_back(carWeight);
}
deque<long long> carQueue;
long long parkingAvail = parkingStateArr.size();
long long res = 0;
for (int i = 0 ; i < carArr.size() * 2; i++) {
// cout << res << endl;
long long carId;
cin >> carId;
// cout << carId << endl;
// carId--;
if (carId > 0) { // In
if (parkingAvail > 0) {
parkingAvail--;
int idx = -1;
for (int i = 0 ; i < parkingStateArr.size(); i++) {
if (parkingStateArr[i] == -1) {
idx = i;
break;
}
}
// cout << parkingPriceArr[idx] * carArr[carId] << endl;
res += parkingPriceArr[idx] * carArr[carId - 1];
parkingStateArr[idx] = carId - 1;
} else {
carQueue.push_back(carId);
}
} else { // Out
parkingAvail++;
int idx = -1;
for (int i = 0 ; i < parkingStateArr.size(); i++) {
if (parkingStateArr[i] == abs(carId) - 1) {
idx = i;
break;
}
}
parkingStateArr[idx] = -1;
}
while (parkingAvail > 0 && carQueue.size() > 0) {
// cout << "BEBE" << endl;
int carId = carQueue[0];
carQueue.pop_front();
parkingAvail--;
int idx = -1;
for (int i = 0 ; i < parkingStateArr.size(); i++) {
if (parkingStateArr[i] == -1) {
idx = i;
break;
}
}
// cout << parkingPriceArr[idx] * carArr[carId] << endl;
res += parkingPriceArr[idx] * carArr[carId - 1];
parkingStateArr[idx] = carId - 1;
}
}
cout << res << endl;
}
