#include<bits/stdc++.h>

 #define pa pair<int,int>

 #define ll long long

 using namespace std;

 const int maxn=,maxm=;

 inline ll rd(){

     ll x=;char c=getchar();int neg=;

     while(c<''||c>''){if(c=='-') neg=-;c=getchar();}

     while(c>=''&&c<='') x=x*+c-'',c=getchar();

     return x*neg;

 }

 int N,M,m[];

 int f[maxm][maxm][maxm][maxm];

 bool flag[][][maxm];

 int v[maxn];

 inline void sm(int &a,int b){

     if(b>a) a=b;

 }

 int main(){

     int i,j,k;

     N=rd(),M=rd();

     for(i=;i<N;i++) v[i]=rd();

     for(i=;i<=M;i++) m[rd()]++;

     f[][][][]=v[];

     for(int x1=;x1<=m[];x1++){

         for(int x2=;x2<=m[];x2++){

             for(int x3=;x3<=m[];x3++){

                 for(int x4=;x4<=m[];x4++){

                     int now=f[x1][x2][x3][x4],pos=x1*+x2*+x3*+x4*;

                     if(x1<m[]) sm(f[x1+][x2][x3][x4],now+v[pos+]);

                     if(x2<m[]) sm(f[x1][x2+][x3][x4],now+v[pos+]);

                     if(x3<m[]) sm(f[x1][x2][x3+][x4],now+v[pos+]);

                     if(x4<m[]) sm(f[x1][x2][x3][x4+],now+v[pos+]);

                 }

             }

         }

     }printf("%d\n",f[m[]][m[]][m[]][m[]]);

     return ;

 }