#include <bits/stdc++.h> using namespace std; const int N = 2222; int n, m, ans, r[N], w[N], v[N]; queue<int> q; signed main(){ ios_base::sync_with_stdio(false); cin.tie(NULL); cin >> n >> m; for(int i = 1;i<=n;i++) cin >> r[i]; for(int i = 1;i<=m;i++) cin >> w[i]; for(int i = 1;i<=2*m;i++){ int x; cin >> x; if(x > 0){ q.push(x); while(!q.empty()){ bool f = 1; for(int i = 1;i<=n;i++){ if(v[i] == 0){ f = 0; v[i] = q.front(); ans += r[i] * w[v[i]]; q.pop(); break; } } if(f) break; } }else{ for(int i = 1;i<=n;i++){ if(v[i] == -x){ v[i] = 0; break; } } while(!q.empty()){ bool f = 1; for(int i = 1;i<=n;i++){ if(v[i] == 0){ f = 0; v[i] = q.front(); ans += r[i] * w[v[i]]; q.pop(); break; } } if(f) break; } } } cout << ans; }