#include<bits/stdc++.h>
#include<fstream>
using namespace std;
//ifstream fin("INTERNET.INP");
//ofstream fout("INTERNET.OUT");
#define ll long long
#define vt vector
#define pb push_back
#define fi first
#define se second
#define forr(i, a, b) for(int i = a; i < b; i++)
#define dorr(i, a, b) for(int i = a; i >= b; i--)
#define pii pair<int, int>
#define pll pair<ll, ll>
//#define int long long
typedef unsigned long long ull;
const int mxn = 2e3, sq = 317, mxv = 1e4;
const ll mx = 1e9;
const ll p[4] = {2, 3, 5, 7};
int n, m;
int r[mxn + 1], w[mxn + 1], pos[mxn + 1];
set<int>s;
queue<int>q;
signed main()
{
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
cin >> n >> m;
for(int i = 1; i <= n; i++){
cin >> r[i]; s.insert(i);
}
int ans = 0;
for(int i = 1; i <= m; i++)cin >> w[i];
for(int i = 0; i < 2 * m; i++){
int x; cin >> x;
if(x > 0){
if(s.size()){
int p = *s.begin(); s.erase(p); pos[x] = p;
ans += w[x] * r[p];
}else{
q.push(x);
}
}else{
x = -x; int nw = pos[x];
if(q.size()){
int cr = q.front(); q.pop(); pos[cr] = nw; ans += w[cr] * r[nw];
}else{
s.insert(nw);
}
}
}
cout << ans;
return 0;
}
