#include <fstream>
#include <vector>
#include <queue>
#include <cstring>
#define INF 0x3f3f3f3f
#define Mmax 2003
#define Nmax 18
using namespace std;
ifstream fin("ubuntzei.in");
ofstream fout("ubuntzei.out");
int n,m,v[Nmax],dist[Mmax],dp[(1<<Nmax)][Nmax],k;
struct ceva{
    int nod,cost;
    bool operator <(const ceva &val)const{
        return cost>val.cost;
    }
};
vector <ceva> G[Mmax],G1[Mmax];
priority_queue <ceva> q;
void dijkstra(int start)
{
    memset(dist,INF,sizeof dist);
    q.push({start,0});
    dist[start]=0;
    while (!q.empty())
    {
        int x=q.top().nod;
        int y=q.top().cost;
        q.pop();
        if (y!=dist[x]) continue;
        for (auto i:G[x])
        {
            if (y+i.cost<dist[i.nod])
            {
                dist[i.nod]=y+i.cost;
                q.push({i.nod,dist[i.nod]});
            }
        }
    }
}
void rezolvare()
{
    int stare,i,j;
    for (stare=1;stare<=((1<<k)-1);stare++)
    {
        for (i=0;i<k;i++)
        {
            if (((1<<i)&stare)>0 && dp[stare][i]!=INF)
            {
                for (auto j:G1[i])
                {
                    if (((1<<j.nod)&stare)==0)
                    {
                        dp[stare+(1<<j.nod)][j.nod]=min(dp[stare+(1<<j.nod)][j.nod],dp[stare][i]+j.cost);
                    }
                }
            }
        }
    }
}
int main()
{
    int i,j,a,b,c;
    fin>>n>>m;
    fin>>k;
    v[0]=1;
    for (i=1;i<=k;i++)
        fin>>v[i];
        k++;
        v[k]=n;
    for (i=1;i<=m;i++){
        fin>>a>>b>>c;
        G[a].push_back({b,c});
        G[b].push_back({a,c});
    }

    for (i=0;i<=k;i++)
    {
        dijkstra(v[i]);
        for (int j=0;j<=k;j++)
        {
            if (i!=j)
            G1[i].push_back({j,dist[v[j]]});
        }
    }
    k++;
    memset(dp,INF,sizeof dp);
    dp[1][0]=0;
    rezolvare();
    fout<<dp[(1<<k)-1][k-1];
    return 0;
}