#include <iostream>
#include <fstream>
#include <vector>
#include <algorithm>
#include <queue>

///#include <tryhardmode>
///#include <GODMODE::ON>

using namespace std;

ifstream fin ("ubuntzei.in");
ofstream fout ("ubuntzei.out");

#define int long long

const int INF=2e9;
const int NMAX=2e3+5;
const int MASK=20;

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

int dist[NMAX];
int dp2[NMAX][NMAX];
int dp[(1<<MASK)][MASK];
int c[NMAX];

void dijkstra(int p)
{
    priority_queue<pair<int,int>>pq;
    pq.push(make_pair(0,p));
    dist[p]=0;
    while(!pq.empty())
    {
        pair<int,int>p=pq.top();
        pq.pop();
        for(auto i:v[p.second])
        {
            if(dist[i.first]>dist[p.second]+i.second)
            {
                dist[i.first]=dist[p.second]+i.second;
                pq.push(make_pair(-dist[i.first],i.first));
            }
        }
    }
}

signed main()
{
    int n,m,i,j,k,mask;
    fin>>n>>m>>k;
    for(i=1;i<=k;i++)
        fin>>c[i];
    c[0]=1;
    c[k+1]=n;
    for(i=1;i<=m;i++)
    {
        int x,y,cost;
        fin>>x>>y>>cost;
        v[x].push_back(make_pair(y,cost));
        v[y].push_back(make_pair(x,cost));
    }
    for(i=0;i<=k+1;i++)
    {
        for(j=1;j<=n;j++)
            dist[j]=INF;
        dijkstra(c[i]);
        for(j=0;j<=k+1;j++)
        {
            dp2[i][j]=dist[c[j]];
            dp2[j][i]=dist[c[j]];
        }
        dp2[i][i]=INF;
    }
    for(i=0;i<(1<<(k+2));i++)
        for(j=0;j<=k+1;j++)
            dp[i][j]=INF;
    for(i=0;i<=k+1;i++)
        dp[0][i]=0;
    dp[1][0]=0;
    for(mask=1;mask<(1<<(k+2));mask++)
    {
        for(i=0;i<=k+1;i++)
        {
            if(mask & (1<<i))
            {
                for(j=0;j<=k+1;j++)
                {
                    if(dp[mask][i]>dp[mask^(1<<i)][j]+dp2[i][j])
                        dp[mask][i]=dp[mask^(1<<i)][j]+dp2[i][j];
                }
            }
        }
    }
    fout<<dp[(1<<(k+2))-1][k+1];
    return 0;
}