#include <bits/stdc++.h>
#define ll long long
#define pb push_back
#define INF 2e9
using namespace std;

ifstream f("ubuntzei.in");
ofstream g("ubuntzei.out");
int n,m,k,v[20],dist[20][20],d[2005];
vector<pair<int,int> > adj[2005];
int dp[(1<<18)+5][18];
struct Comp
{
     bool operator()(const int a,const int b)
    {
        return d[a]>d[b];
    }
};
void djikstra(int node)
{
    priority_queue<int,vector<int>,Comp> Q;
    for(int i=1; i<=n; i++)
    {
        d[i]=INF;
    }
    d[node]=0;
    Q.push(node);
    while(!Q.empty())
    {
        int x=Q.top();
        Q.pop();
        for(int i=0; i<adj[x].size(); i++)
        {
            int vec=adj[x][i].first;
            int cost=adj[x][i].second;
            if(d[vec]>d[x]+cost)
            {
                d[vec]=d[x]+cost;
                Q.push(vec);
            }

        }
    }


}
int main()
{
    f>>n>>m>>k;
    for(int i=1; i<=k; i++)
    {
        f>>v[i];
    }
    v[0]=1;
    v[k+1]=n;
    for(int i=1; i<=m; i++)
    {
        int x,y,c;
        f>>x>>y>>c;
        adj[x].pb({y,c});
        adj[y].pb({x,c});
    }
    for(int i=0; i<=k+1; i++)
    {
        djikstra(v[i]);
        for(int j=0; j<=k+1; j++)
        {
            dist[i][j]=d[v[j]];
            //g<<dist[i][j]<<" ";
        }
        if(i)
            dist[i][i]=5000000;
       // g<<'\n';
    }
    for(int i=0;i<(1<<(k+2));i++)
    {
        for(int j=0;j<=k+1;j++)
        {
            dp[i][j]=5000000;
        }
    }
    dp[0][0]=0;
    for(int i=0;i<(1<<(k+2));i++)
    {
      for(int j=0;j<=k+1;j++)
      {
          if(i&(1<<j))
          {
              for(int d=0;d<=k+1;d++)
              {
                  dp[i][j]=min(dp[i][j],dp[i^(1<<j)][d]+dist[d][j]);
                  //cout<<dp[i][j]<<" ";
              }
          }
          //cout<<'\n';
      }

    }
    g<<dp[(1<<k+2)-1][k+1];
}