#include <bits/stdc++.h>
using namespace std;
int main(){
int n,m,ans = 0; cin >> n >> m;
int space[n+1], car[m+1], curs[n+1] = {0}, curc[m+1] = {0}, available = n;
queue<int> q;
for(int i = 1; i <= n; i++) cin >> space[i];
for(int i = 1; i <= m; i++) cin >> car[i];
for(int i = 1; i <= 2*m; i++){
int cmd; cin >> cmd;
if(cmd > 0){
int ptr = 1;
while(curs[ptr] != 0 && ptr < n) ptr++;
if(ptr == n){
q.push(cmd);
}else{
curc[cmd] = ptr;
curs[ptr] = cmd;
ans += car[cmd] * space[ptr];
available--;
}
}else{
curs[curc[cmd*-1]] = 0;
curc[cmd*-1] = 0;
available++;
}
while(!q.empty()){
if(available == 0) break;
int ptr = 1;
while(curs[ptr] != 0 && ptr < n) ptr++;
curc[q.front()] = ptr;
curs[ptr] = q.front();
ans += car[q.front()] * space[ptr];
available--;
q.pop();
}
}
cout << ans << endl;
}
