#include <bits/stdc++.h>
using namespace std;
int n, a[107], b[107], c[107], score, vis[107];
template <typename type_of_scan>
inline void scan(type_of_scan &x) {
  type_of_scan f = 1;
  x = 0;
  char s = getchar();
  while (s < '0' || s > '9') {
    if (s == '-') f = -1;
    s = getchar();
  }
  while (s >= '0' && s <= '9') {
    x = x * 10 + s - '0';
    s = getchar();
  }
  x *= f;
}
template <typename Tops, typename... tops>
inline void scan(Tops &x, tops &...X) {
  scan(x), scan(X...);
}
int main() {
  scan(n);
  for (int i = 1; i <= n; i++) scan(a[i]);
  for (int i = 1; i <= n; i++) scan(b[i]);
  for (int j = 1; j <= n - 1; j++) scan(c[j]);
  for (int i = 1; i <= n; i++) {
    score += b[a[i]];
    vis[a[i]] = 1;
    if (vis[a[i] - 1]) score += c[a[i] - 1];
  }
  printf("%d\n", score);
}
