#include <bits/stdc++.h>
// mrrrow meeow :3
// go play vivid/stasis now! https://vividstasis.gay
#define fo(i, a, b) for (auto i = (a); i < (b); i++)
#define of(i, a, b) for (auto i = (b); i-- > (a);)
#define f first
#define s second
#define pb push_back
#define lb lower_bound
#define ub upper_bound
#define be(a) a.begin(), a.end()
using namespace std;
int ____init = [] {
ios::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
return 0;
}();
int r[100], u[100];
int w[2000], cm[2000];
int main() {
int n, m; cin >> n >> m;
fo(i, 0, n) cin >> r[i];
fo(i, 0, m) cin >> w[i];
int used = 0;
int res = 0;
queue<int> cars;
fo(_, 0, 2*m) {
int c; cin >> c;
if (c > 0) {
c--;
cars.push(c);
} else {
c = -c - 1;
res += r[cm[c]] * w[c];
u[cm[c]] = false;
used--;
}
while (cars.size() && used < n) {
fo(i, 0, n) {
if (!u[i]) {
cm[cars.front()] = i, cars.pop(), u[i] = true, used++;
break;
}
}
}
}
cout << res;
}
