#include <bits/stdc++.h>
#define startt ios_base::sync_with_stdio(false);cin.tie(0);
typedef long long ll;
using namespace std;
#define vint vector<int>
#define all(v) v.begin(), v.end()
#define MOD 1000000007
#define MOD2 998244353
#define MX 1000000000
#define MXL 1000000000000000000
#define PI (ld)2*acos(0.0)
#define nax 200005
#define pb push_back
#define sc second
#define fr first
#define int long long
#define endl '\n'
#define ld long double
#define NO cout << "NO" << endl
#define YES cout << "YES" << endl
int ceildiv(int one, int two) {if (one % two == 0) {return one / two;}else {return one / two + 1;}} int power(int n, int pow, int m) {if (pow == 0) return 1;if (pow % 2 == 0) {ll x = power(n, pow / 2, m);return (x * x) % m;}else return (power(n, pow - 1, m) * n) % m;} int gcd(int a, int b) { if (!b)return a; return gcd(b, a % b);} int factorial(int n, int mod) {if (n > 1)return (n * factorial(n - 1, mod)) % mod; else return 1;} int lcm(int a, int b) {return (a * b) / gcd(a, b);} vector<int> read(int n) {vector<int> a; for (int i = 0; i < n; i++) { int x; cin >> x; a.pb(x);} return a;}//ssense
void solve()
{
int n, m;
cin >> n >> m;
vint r = read(n);
vint w = read(m);
set<int> available;
for(int i = 0; i < n; i++)
{
available.insert(i);
}
deque<int> queue;
map<int, int> mp;
int ans = 0;
for(int i = 0; i < 2*m; i++)
{
int now;
cin >> now;
if(now > 0)
{
if(available.size() == 0)
{
queue.pb(now);
}
else
{
int garage = *available.begin();
ans+=w[now-1]*r[garage];
mp[now] = garage;
available.erase(available.begin());
}
}
else
{
now = abs(now);
available.insert(mp[now]);
if(!queue.empty())
{
int rep = queue.front();
int garage = *available.begin();
ans+=w[rep-1]*r[garage];
mp[rep] = garage;
available.erase(available.begin());
queue.pop_front();
}
}
}
cout << ans << endl;
}
int32_t main(){
startt;
int t = 1;
//cin >> t;
while (t--)
{
solve();
}
}
/*
3 4
2
3
5
200
100
300
800
3
2
-3
1
4
-4
-2
-1
*/
