#include <cstdio>
#include <vector>
#include <queue>

#define KMAX 20
#define NMAX 2050
#define NR 1<<20
#define INF 0x3f3f3f3f

using namespace std;

int n,m,k,x,y,d,nod[KMAX];
int best[NMAX],cost[NMAX][NMAX],mi[KMAX][NR];

queue <int>q;
vector <pair <int ,int > >v[NMAX];

inline void dijkstra(int nod)
{
    for (int i=0;i<=n;i++)
      best[i]=INF;

    best[nod]=0;
    q.push(nod);

    while (!q.empty())
     {
        nod=q.front();
        q.pop();
        for (vector <pair <int ,int> >::iterator it=v[nod].begin();it!=v[nod].end();it++)
          if (best[(*it).first]>best[nod]+(*it).second)
           {
               q.push((*it).first);
               best[(*it).first]=best[nod]+(*it).second;
           }
     }
}
inline void solve()
{
    for (int i=0;i<=k;i++)
     {
        dijkstra(nod[i]);
        for (int j=0;j<=k;j++)
          cost[i][j]=best[nod[j]];
     }
    for (int i=1;i<=(1<<k+1)-1;i++)
       for (int j=0;j<=k;j++)
          mi[j][i]=INF;
    for (int i=1;i<=(1<<k+1)-1;i++)
       for (int j=0;j<=k;j++)
         if (i&(1<<j))
           for (int jj=0;jj<=k;jj++)
             if (i&(1<<jj))
               mi[j][i]=((mi[j][i]<mi[jj][i^(1<<j)]+cost[j][jj])?mi[j][i]:mi[jj][i^(1<<j)]+cost[j][jj]);
    printf("%d",mi[k][(1<<k+1)-1]);
}
int main()
{
    freopen("ubuntzei.in","r",stdin);
    freopen("ubuntzei.out","w",stdout);

    scanf("%d %d %d",&n,&m,&k);
    for (int i=1;i<=k;i++)
      scanf("%d ",&nod[i]);
    nod[0]=1;
    nod[++k]=n;
    for (int i=1;i<=m;i++)
      {
          scanf("%d %d %d",&x,&y,&d);
          v[x].push_back(make_pair(y,d));
          v[y].push_back(make_pair(x,d));
      }
    if (k==1)
      dijkstra(1),printf("%d",best[n]);
    else
      solve();

    fclose(stdin);
    fclose(stdout);
}