#include <bits/stdc++.h>
int main(void) {
  int N, score = 0;
  scanf("%d", &N);
  int A[N], B[N], C[N - 1];
  for (int j = 0; j < N; j++) {
    scanf("%d", &A[j]);
  }
  for (int j = 0; j < N; j++) {
    scanf("%d", &B[j]);
  }
  for (int j = 0; j < N - 1; j++) {
    scanf("%d", &C[j]);
  }
  for (int i = 0; i < N; i++) {
    score += B[i];
  }
  for (int i = 0; i < N - 1; i++) {
    if (A[i + 1] - A[i] == 1) {
      score += C[A[i]];
    }
  }
  printf("%d", score);
  return 0;
}
