#include <bits/stdc++.h>   using namespace std;   const int DIM = 1005;   bitset<DIM> oki;   int val[DIM], nxt[DIM];   int main(void) {     ios ::sync_with_stdio(false);     cin.tie();     cout.tie();     int n, m, ans = 0;     cin >> n >> m;     for (int i = 1; i <= n; ++i) cin >> val[i], nxt[i] = -1;     for (int i = 1; i <= m; ++i) {       int x;       cin >> x;       for (int j = 1; j <= n; ++j)         if (nxt[x] < nxt[j]) ans += val[j];       nxt[x] = i;     }     cout << ans << endl;     return 0;   }   