import core.bitop;
import std.algorithm;
import std.ascii;
import std.bigint;
import std.conv;
import std.functional;
import std.math;
import std.numeric;
import std.range;
import std.stdio;
import std.string;
import std.random;
import std.typecons;
import std.container;

alias sread = () => readln.chomp();
ulong MOD = 1_000_000_007;
ulong INF = 1_000_000_000_000;
alias Goods = Tuple!(long, "w", long, "v");

T lread(T = long)()
{
    return readln.chomp.to!T();
}

T[] aryread(T = long)()
{
    return readln.split.to!(T[])();
}

void scan(TList...)(ref TList Args)
{
    auto line = readln.split();
    foreach (i, T; TList)
    {
        T val = line[i].to!(T);
        Args[i] = val;
    }
}

void main()
{
    auto n = lread();
    auto a = aryread();
    auto b = aryread();
    auto c = aryread();
    long cost, prev = INF;
    foreach (e; a)
    {
        cost += b[e - 1];
        if (e == prev + 1)
            cost += c[prev - 1];
        prev = e;
    }
    cost.writeln();
}
