Problem:
Score : 200 points

Problem Statement

Takahashi went to an all-you-can-eat buffet with N kinds of dishes and ate all of them (Dish 1, Dish 2, \ldots, Dish N) once.

The i-th dish (1 \leq i \leq N) he ate was Dish A_i.

When he eats Dish i (1 \leq i \leq N), he gains B_i satisfaction points.

Additionally, when he eats Dish i+1 just after eating Dish i (1 \leq i \leq N - 1), he gains C_i more satisfaction points.

Find the sum of the satisfaction points he gained.

Constraints

All values in input are integers.

2 \leq N \leq 20

1 \leq A_i \leq N

A_1, A_2, ..., A_N are all different.

1 \leq B_i \leq 50

1 \leq C_i \leq 50

Input

Input is given from Standard Input in the following format:

N
A_1 A_2 ... A_N
B_1 B_2 ... B_N
C_1 C_2 ... C_{N-1}

Output

Print the sum of the satisfaction points Takahashi gained, as an integer.

Sample Input 1

3
3 1 2
2 5 4
3 6

Sample Output 1

14

Takahashi gained 14 satisfaction points in total, as follows:

First, he ate Dish 3 and gained 4 satisfaction points.

Next, he ate Dish 1 and gained 2 satisfaction points.

Lastly, he ate Dish 2 and gained 5 + 3 = 8 satisfaction points.

Sample Input 2

4
2 3 4 1
13 5 8 24
45 9 15

Sample Output 2

74

Sample Input 3

2
1 2
50 50
50

Sample Output 3

150

Solution in C++14 (GCC 5.4.1) (judge verdict: Accepted)

/* ****mittal**** */
#include<bits/stdc++.h>
#define ll          long long int 
#define pb          push_back
#define endl        '\n'
#define pii         pair<ll int,ll int>
#define vi          vector<ll int>
#define all(a)      (a).begin(),(a).end()
#define F           first
#define S           second
#define sz(x)       (ll int)x.size()
#define hell        1000000007
#define rep(i,a,b)    for(ll int i=a;i<b;i++)
#define repr(i,a,b)   for(ll int i=a;i>=b;i--)
#define lbnd    lower_bound
#define ubnd        upper_bound
#define mp          make_pair
using namespace std;
 
#define N  100005
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int TESTS=1;   
   //  cin>>TESTS;
    while(TESTS--)
    {
       ll n;
       cin>>n;
       ll a[28],b[28],c[28];
       for(int i=1;i<=n;i++)
           cin>>a[i];
       for(int i=1;i<=n;i++)
       {
             cin>>b[i];
       }
       a[0]=500;
       for(int i=1;i<=n-1;i++)
           cin>>c[i];
       ll ans=0;
       for(int i=1;i<=n;i++)
       {
           ans+=b[a[i]];
           if(a[i]==a[i-1]+1)
               ans+=c[a[i-1]];
       }
       cout<<ans;
    }
    return 0;
}