//Coded by Chirath Nirodha
#include<bits/stdc++.h>
using namespace std;
#include<ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
#define MP make_pair
#define PB push_back
#define F first
#define S second
#define I insert
#define P push
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> indexed_tree;
const ll mod=1e9+7;
inline void io(){
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
}
void solve(){
io();
int n,m;cin>>n>>m;
int r[n],w[m];
for(int i=0;i<n;i++)cin>>r[i];
for(int i=0;i<m;i++)cin>>w[i];
bool park[n];memset(park,false,sizeof(park));
int place[m];
ll ans=0;
queue<int> q;
for(int i=0;i<2*m;i++){
int x;cin>>x;
if(x>0){
x--;
bool found=false;
for(int j=0;j<n;j++)
if(!park[j]){
park[j]=true;
place[x]=j;
ans+=w[x]*r[j];
found=true;
break;
}
if(!found)q.P(x);
}
else{
x++;x*=-1;
park[place[x]]=false;
if(!q.empty()){
int c=q.front();q.pop();
park[place[x]]=true;
place[c]=place[x];
ans+=w[c]*r[place[x]];
}
}
}
cout<<ans<<endl;
}
int main(){
io();
solve();
}
