#include<cstdio>#include<iostream>#include<cstring>using namespace std;int vis[505],b[1005],w[505];int main(){    int n,m,sum = 0;    cin >> n >> m;    for(int i = 1;i <= n;i++)        cin >> w[i];    for(int i = 1;i <= m;i++)    {        memset(vis,0,sizeof(vis));        cin >> b[i];        for(int j = i-1;j > 0;j--)        {            if(b[j] == b[i])                break;            if(!vis[b[j]])            {                sum += w[b[j]];                vis[b[j]] = 1;            }        }    }    cout << sum << endl;    return 0;}