#pragma GCC optimize("Ofast","unroll-loops")
// #pragma GCC target("avx2,fma")
#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,b) for (__typeof(a) i=(a); i<(b); ++i)
#define iter(it,c) for (__typeof((c).begin()) \
it = (c).begin(); it != (c).end(); ++it)
#define riter(it,c) for (__typeof((c).rbegin()) \
it = (c).rbegin(); it != (c).rend(); ++it)
typedef pair<int, int> ii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef long long ll;
#define pb push_back
#define fs first
#define sc second
const int INF = ~(1<<31);
const double EPS = 1e-9;
const double pi = acos(-1);
typedef unsigned long long ull;
typedef vector<vi> vvi;
typedef vector<vii> vvii;
template <class T> T smod(T a, T b) {
return (a % b + b) % b; }
int main() {
int n, m;
cin >> n >> m;
vector<ll> p(m+1), w(m+1), r(n+1);
priority_queue<int, vi, greater<int>> pq;
queue<int> q;
ll sm = 0;
rep(i, 0, n) {
cin >> r[i+1];
pq.push(i+1);
}
rep(i, 0, m) {
cin >> w[i+1];
}
rep(i, 0, 2 * m) {
int temp;
cin >> temp;
if (temp < 0) {
pq.push(p[abs(temp)]);
} else {
q.push(temp);
}
while (!q.empty() && !pq.empty()) {
int front = q.front();
int place = pq.top();
q.pop(); pq.pop();
sm += w[front] * r[place];
// cout << front << ' ' << place << ' ' << sm << endl;
p[front] = place;
}
}
cout << sm << endl;
return 0;
}
