#include <stdio.h>
#include <vector>
#include <queue>
#include <algorithm>
using namespace std;

#define Nmax 2005
#define Kmax 17
#define inf 1073741824

vector < pair<int, int> > graph[Nmax];
int p[Kmax], dist[Nmax];
int edges[Kmax + 2][Kmax + 2];
int mat[1 << Kmax][Kmax];
int n, m, k;

struct cmp{
    bool operator() (const int &i, const int &j){
        return dist[i] > dist[j];
    }
};
priority_queue <int , vector <int>, cmp> heap;

inline int min(int a, int b){
    return (a < b) ? a : b;
}

void read(){
    freopen("ubuntzei.in", "r", stdin);
    int u, v, c;

    scanf("%d %d %d", &n, &m, &k);
    for (int i = 1; i <= k; ++i)
        scanf("%d", &p[i]);
    p[0] = 1;
    p[k + 1] = n;
    ++k;
    for (int i = 1; i <= m; ++i){
        scanf("%d %d %d", &u, &v, &c);
        graph[u].push_back( make_pair(v, c) );
        graph[v].push_back( make_pair(u, c) );
    }
    fclose(stdin);
}

void dijkstra(int s){
    vector < pair <int, int> >::iterator it;
    int u;

    for (int i = 1; i <= n; ++i)
        dist[i] = inf;
    dist[s] = 0;
    heap.push(s);

    while ( !heap.empty() ){
        u = heap.top();
        heap.pop();

        for (it = graph[u].begin(); it != graph[u].end(); ++it)
            if (dist[it->first] > dist[u] + it->second){
                dist[it->first] = dist[u] + it->second;
                heap.push(it->first);
            }
    }
}

void solve(){
    for (int i = 0; i <= k; ++i){
        dijkstra(p[i]);
        for (int j = 0; j <= k; ++j)
            edges[i][j] = dist[ p[j] ];
    }
    for (int i = 0; i < 1 << (k + 1); ++i)
        for (int j = 0; j <= k; ++j)
            mat[i][j] = inf;
    mat[1][0] = 0;
    for (int i = 0; i < 1 << (k + 1); ++i)
        for (int j = 0; j <= k; ++j)
            if ((1 << j) & i)
                for (int ii = 0; ii <= k; ++ii)
                    if ((1 << ii) & i)
                        mat[i][j] = min(mat[i][j], mat[i ^ (1 << j)][ii] + edges[j][ii]);
    printf("%d", mat[(1 << (k + 1)) - 1][k]);
    fclose(stdout);
}

int main(){
    freopen("ubuntzei.out", "w", stdout);
    read();
    solve();

    return 0;
}