50 50
75 71 23 37 28 23 69 75 5 62 3 11 96 100 13 50 57 51 8 90 4 6 84 27 11 89 95 81 10 62 48 52 69 87 97 95 30 74 21 42 36 64 31 80 81 50 56 53 33 99
26 30 5 33 35 29 6 15 36 17 32 16 14 1 29 34 22 40 12 42 38 48 39 50 13 47 18 43 10 8 49 45 11 31 21 37 46 28 20 41 2 7 9 24 27 23 3 44 15 14
 10 10
61 59 97 16 2 94 57 48 91 93
2 8 6 5 3 1 3 4 9 10
 2 1
1 2
1
 3 3
10 20 30
1 2 3
 50 60
86 57 45 93 17 12 40 10 47 80 18 80 3 9 6 55 13 99 5 76 4 70 100 55 27 91 71 3 65 93 41 74 80 56 90 50 58 13 71 9 47 52 26 73 72 21 15 81 88 28
40 32 5 16 49 23 3 17 14 10 1 15 1 21 28 22 13 45 12 25 44 48 46 32 36 43 11 8 49 7 7 35 10 14 39 4 42 10 30 27 1 17 31 15 8 41 44 33 25 26 19 18 29 37 50 6 36 38 47 9
 2 7
20 30
1 1 1 2 2 2 2
 2 2
10 12
2 1
 5 1
16 87 36 16 81
3
 2 3
20 30
1 1 1
 2 10
39 26
1 1 2 2 2 2 2 2 1 2

63929
 2137
 0
 40
 62514
 20
 12
 0
 0
 104

#include <bits/stdc++.h>
using namespace std;
int n, m;
int w[1200];
int b[1200];
int a[1200];
int c[1200];
int use[1200];
int cmp1(const void *p1, const void *p2) { return *(int *)p1 - *(int *)p2; }
int cmp2(const void *p1, const void *p2) { return *(int *)p2 - *(int *)p1; }
void solve() {
  int i, j, k, idx;
  for (i = 1; i <= n; i++) {
    a[i] = 0;
    use[i] = false;
  }
  j = 1;
  for (i = 1; i <= n; i++) scanf("%d", &w[i]);
  for (i = 1; i <= m; i++) {
    scanf("%d", &b[i]);
    if (!use[b[i]]) {
      use[b[i]] = true;
      c[j++] = b[i];
    }
  }
  i = 1;
  while (j <= n && i <= n) {
    if (!use[i]) {
      c[j++] = i;
      use[i] = true;
    }
    i++;
  }
  for (i = 1; i <= m; i++) {
    k = 0;
    idx = 0;
    for (j = 1; j <= n; j++) {
      if (c[j] == b[i]) {
        idx = j;
        break;
      }
      a[c[j]]++;
    }
    if (idx == 0) continue;
    for (j = idx; j > 1; j--) {
      c[j] = c[j - 1];
    }
    c[1] = b[i];
  }
  w[0] = -10000;
  a[0] = 1000000000;
  k = 0;
  for (i = 1; i <= n; i++) {
    k += (a[i] * w[i]);
  }
  printf("%d\n", k);
}
int main() {
  while (scanf("%d %d", &n, &m) != EOF) {
    solve();
  }
  return 0;
}
