#include<stdio.h>
#include<vector>
#include<queue>
#include<algorithm>

using namespace std;

FILE *in, *out;

const int MAXN = 2001;
const int INF = 0x7fffffff;
const int STARI = (1 << 17);

struct edge
{
    const bool operator <(const edge &oth)const
    {
        return c > oth.c;
    }
    int nod, c;
};

vector <edge> g[MAXN];
priority_queue <edge> q;

vector <int> spc;

int viz[MAXN];
int dj[MAXN], dbu[STARI][17], dist[17][17];
int n, m, k;


void cleandjk()
{
    for(int i = 0; i < MAXN; i++)
    {
        viz[i] = false;
        dj[i] = INF;
    }
}

void djk(int st)
{
    edge nou;
    //q.erase();
    dj[st] = 0;
    nou.nod = st;
    nou.c = 0;
    q.push(nou);

    while(!q.empty())
    {
        edge cur = q.top();
        q.pop();

        if(!viz[cur.nod])
        {
            viz[cur.nod] = true;
            for(auto &it : g[cur.nod])
            {
                int d = it.c + dj[cur.nod];
                if(d < dj[it.nod])
                {
                    edge nou;
                    nou.nod = it.nod;
                    nou.c = d;
                    q.push(nou);
                    dj[it.nod] = d;
                }
            }
        }
    }
}

void printmat()
{
    for(int i = 1; i < (1 << (k + 2)); i++) {
        for(int j = 0; j < k + 2; j++) {
            printf("%10d ", dbu[i][j]);
        }
        printf("\n");
    }
    printf("-------------------------------\n");
}

void dst(int nod)
{

    for(int i = 1; i < (1 << (k + 2)); i++) {
        for(int j = 0; j < k + 2; j++) {
            dbu[i][j] = INF;
        }
    }

    dbu[1][nod] = 0;

    for(int i = 1; i < (1 << (k + 2)); i++) {
        for(int j = 0; j < k + 2; j++) {
            if(dbu[i][j] != INF) {

                //printmat();

                for(int t = 1; t < k + 2; t++) {
                    int xp = (1 << t);
                    if((i & xp) == 0) {
                        dbu[i + xp][t] = min(dbu[i + xp][t], dbu[i][j] + dist[j][t]);
                    }
                }
            }
        }
    }
}






int main ()
{

    in = fopen("ubuntzei.in", "r");
    out = fopen("ubuntzei.out", "w");

    fscanf(in, "%d%d%d", &n, &m, &k);
    //printf("EJGAY");


    spc.push_back(0);
    spc.push_back(n - 1);

    for(int i = 0; i < k; i++)
    {
        int x;
        fscanf(in, "%d", &x);
        x--;
        spc.push_back(x);
    }

    sort(spc.begin(), spc.end());

    for(int i = 0; i < m; i++)
    {
        int a, b, c;
        fscanf(in, "%d %d %d", &a, &b, &c);
        a--;
        b--;
        edge nou;
        nou.nod = b;
        nou.c = c;
        g[a].push_back(nou);
        nou.nod = a;
        g[b].push_back(nou);
    }

    for(int i = 0; i < k + 2; i++)
    {
        cleandjk();
        djk(spc[i]);
        for(int j = 0; j < k + 2; j++)
        {
            if(i != j)
            {
                dist[i][j] = dj[spc[j]];
            }
        }
    }

    dst(0);

    fprintf(out, "%d", dbu[(1 << (k + 2)) - 1][k + 1]);

    fclose(in);
    fclose(out);

    return 0;
}