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

using namespace std;

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

#define limn 2010
#define limk 20
#define inf 2e9
int n,m,k;
vector <pair<int, int>> G[limn];
int ini[limk],  path[limn][limn];   /// path[nod][nod]
priority_queue <pair <int, int>> q;
int nod, cost;
int dp[1<<limk][limk];  /// dp[mask_indice nod][indice nod]

int main()
{
    int x,y,c;
    fin>>n>>m;
    fin>>k;
    for (int i=1; i<=k; i++)    fin>>ini[i];
    for (int i=1; i<=m; i++)
    {
        fin>>x>>y>>c;
        G[x].push_back({y,c});
        G[y].push_back({x,c});
    }

    ini[0]=1;
    for (int i=0; i<=k; i++)
    {
        for (int j=1; j<=n; j++)    path[ini[i]][j]=inf;
        path[ini[i]][ini[i]] = 0;
        q.push({0,ini[i]});
        while (!q.empty())
        {
            nod = q.top().second;
            cost = -q.top().first;
            q.pop();
            if (path[ini[i]][nod] != cost)  continue;
            for (auto it:G[nod])
                if (path[ini[i]][it.first] > path[ini[i]][nod] + it.second)
                {
                    path[ini[i]][it.first] = path[ini[i]][nod] + it.second;
                    q.push({-path[ini[i]][it.first], it.first});
                }
        }
    }

    if (k==0)
    {
        fout << path[1][n];
        return 0;
    }

    for (int i=1; i<=k; i++)
        dp[1<<(i-1)][i] = path[1][ini[i]];

    for (int mask=1; mask<(1<<k); mask++)
        for (int i=1; i<=k; i++)
            if (mask & (1<<(i-1)))
                for (int j=1; j<=k; j++)
                    if (j!=i && (mask & (1<<(j-1))))
                        if (!dp[mask][i] || dp[mask][i] > dp[mask-(1<<(i-1))][j] + path[ini[j]][ini[i]])
                            dp[mask][i] = dp[mask-(1<<(i-1))][j] + path[ini[j]][ini[i]];

    int minim=inf;
    int mask=(1<<k)-1;
    for (int i=1; i<=k; i++)
        if (dp[mask][i] && dp[mask][i] + path[ini[i]][n] < minim)
            minim = dp[mask][i] + path[ini[i]][n];
    fout<<minim;

    fout.close();
    return 0;
}