#include <bits/stdc++.h>
#define DIM 2001

using namespace std;

ifstream fin("ubuntzei.in");

ofstream fout("ubuntzei.out");

struct nod{

    int node, value;


    bool operator < (nod x) const{

        return (value > x.value);

    }

};

nod temp;

vector < pair <int, int> > G[5 * DIM];

int dp[(1LL << 16) + 2][20];

int cost[DIM][DIM];

int event[DIM];

int n, m, x, y, z, k, i, mask, q, j, answer = 1e9;

void Dijkstra(int source){

    priority_queue <nod> Q;

    temp.node = source;

    temp.value = 0;

    Q.push(temp);

    for(int i=1;i<=n;i++)

        cost[source][i] = 1e9;

    cost[source][source] = 0;

    while(!Q.empty()){

        int node = Q.top().node;

        int value = Q.top().value;

        Q.pop();

        if(cost[source][node] != value)

            continue;

        vector <  pair <int, int> > :: iterator j;

        for(j = G[node].begin() ; j != G[node].end() ; j++){

            if(cost[source][j -> first] > cost[source][node] + j -> second){

                cost[source][j -> first] = cost[source][node] + j -> second;

                temp.node = j -> first;

                temp.value = cost[source][j -> first];

                Q.push(temp);

            }

        }

    }

}

int main(){

    fin >> n >> m >> k;

    for(i=1;i<=k;i++)

        fin >> event[i];

    event[k + 2] = n;

    event[k + 1] = 1;

    while(m--){

        fin >> x >> y >> z;

        G[x].push_back(make_pair(y, z));

        G[y].push_back(make_pair(x, z));

    }

    for(i=1;i<=k+2;i++)

        Dijkstra(event[i]);

    for(i=1;i<=k;i++)

        for(mask = 1 ; mask <= ((1LL << (k)) - 1) ; mask++)

            dp[mask][i] = 1e9;

    for(i=1;i<=k;i++)

        dp[(1LL << (i - 1))][i] = cost[1][event[i]];


    for(mask = 1 ; mask <= ((1LL << k) - 1) ; mask++){

        if(__builtin_popcount(mask) == 1)

            continue;

        for(j=0;j<k;j++){

            if(((mask >> j) & 1)){

                for(q=0;q<k;q++){

                    if((((mask >> q) & 1)) && q != j)

                        dp[mask][j + 1] = min(dp[mask][j + 1], dp[mask - (1LL << j)][q + 1] + cost[event[q + 1]][event[j + 1]]);

                }

            }

        }

    }

    for(i=1;i<=k;i++)

        answer = min(answer, dp[((1LL << k) - 1)][i] + cost[event[i]][n]);

    if(!k)

        fout << cost[1][n];

    else

        fout << answer;

    return 0;

}