#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");

int n, m, k, u[KMAX], ub[KMAX][KMAX],d[NMAX], dp[KMAX][NSTARI];

struct muchie{
    int vf , cost;
};

class comp{
    public: bool operator()(int  &x, int &y){
            return d[x]>d[y];
    };
};

vector <muchie> g[NMAX];
priority_queue <int,vector<int>, comp> q;


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)
{
    int z, z1;
    bool eheap[NMAX]; //eheap[i]=1, daca i este deja in heap

    for(int i = 1; i <= n; i++) d[i] = INF, eheap[i]=0;

    d[s] = 0;
    q.push(s);
    eheap[s] = 1;
    while(!q.empty()){
        z = q.top();
        q.pop();
        eheap[z] = 0;
        for(unsigned int i = 0; i < g[z].size(); i++)
        {
            z1 = g[z][i].vf;
            if(d[z1] > d[z]+g[z][i].cost){
                d[z1] = d[z]+g[z][i].cost;
                if(!eheap[z1])
                    q.push(z1);
            }
        }
    }
}
int main()
{
    citire();
    //distanta intre ubuntzei
    //u[0]=Cluj, u[k]=Constanta, u[1],u[k-1] celelalte localitati cu 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 <= k; i++)
        for(int j = 0; j < nst; j++)
            dp[i][j] = INF;

    dp[0][1] = 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++)        // caut alt bit 1
                    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[bit][i] = min(dp[bit][i], dp[bit1][i ^ (1<<bit)] + ub[bit1][bit]);
    }

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

}