#include <fstream>
#include <vector>
#include <queue>
using namespace std;

#define NMAX 2005
#define KMAX 20
#define NSTARI (1<<17)+5
#define INF (1<<30)

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

struct muchie{
    int vf , cost;
};

class comp{
    public: bool operator()(muchie &x, muchie &y){
            return x.cost>y.cost;
    };
};
vector <muchie> g[NMAX];
priority_queue <muchie,vector<muchie>, comp> q;
int n, m, k, u[KMAX], ub[KMAX][KMAX],d[NMAX], dp[NSTARI][KMAX];
void citire()
{
    int x, y, c;
    fin >> n >> m >> k;
    for(int i = 1; i <= k; i++)
        fin >> u[i];
    u[0] = 1;
    u[++k] = n;
    for(int i = 1; i <= m; i++){
        fin >> x >> y >> c;
        g[x].push_back({y,c});
        g[y].push_back({x,c});
    }
}

void dijkstra(int s)
{
    muchie z, z1;
    for(int i = 1; i <= n; i++) d[i] = INF;
    d[s] = 0;
    q.push({s,0});
    while(!q.empty()){
        z = q.top();
        q.pop();
        if(d[z.vf]!=z.cost) continue;
        for(unsigned int i = 0; i < g[z.vf].size(); i++)
        {
            z1 = g[z.vf][i];
            if(d[z1.vf] > d[z.vf]+z1.cost){
                d[z1.vf] = d[z.vf]+z1.cost;
                q.push({z1.vf,d[z1.vf]});
            }
        }
    }
}
int main()
{
    citire();
    //distanta intre ubuntzei
    //u[0]=Cluj, u[k]=Constanta, u[1],u[k-1] ceilalti ubuntzei
    for (int i = 0; i <= k ;i++){
        dijkstra(u[i]);     //calculez distantele minime de la u[i] la ceilalti ubuntzei
        for(int j = 0; j <= k; j++)
            ub[i][j] = d[u[j]];
    }

    int nst = 1<<(k+1);  //nr de stari
    for(int i = 0; i < nst; i++)
        for(int j = 0; j <= k; j++)
            dp[i][j] = INF;

    dp[1][0] = 0;
    for(int i = 1; i < nst; i++){
        for(int bit = 0; bit <= k; bit++)
            if((i & (1<<bit)) != 0) //in starea i bitul bit este 1
            for(int bit1 = 0; bit1 <= k; bit1++)
                if((i & (1<<bit1))!=0 && bit1 != bit)// ama ajuns in starea i in ubuntzelul bit,
                                                    // dintr-o stare identica cu i, dar cu bitul bit sters pornind din ubuntzelul bit1
                   dp[i][bit] = min(dp[i][bit], dp[i^(1<<bit)][bit1]+ub[bit1][bit]);
    }

    fout<<dp[nst-1][k];
    return 0;

}