#include <iostream>
#include <vector>
#include <fstream>
#include <queue>
#define Nmax 2005
#define Umax 65536
#define INF 0x3f3f3f3f
using namespace std;

ifstream fin("ubuntzei.in");
ofstream fout("ubuntzei.out");
int cst[Nmax][Nmax], dp[Umax][20],c[Nmax],ans = INF,x,y,z;
vector<pair<int,int> >v[Nmax];

struct op
{
    int nod,cost;

    bool operator < (const op &other) const{
        return cost > other.cost;
    }
};
priority_queue<op>pq;
pair <int, pair<int,int> >p;
int n, m, k;
void parc(int cost, int nod, int tata)
{
    for(int i = 0 ; i < v[nod].size(); i++)
    {
        int fiu = v[nod][i].first;
        if(cst[fiu][tata] > cost + v[nod][i].second)
        {
            cst[fiu][tata] = cost + v[nod][i].second;
            pq.push({fiu,cst[fiu][tata]});
        }

    }
}
int main()
{
    fin >> n >> m;
    fin >> k;

    for(int i = 1; i <= n; i++)
        for(int j = 1; j <= n; j++)
            if(i != j)
            cst[i][j] = INF;

    for(int i = 0; i < k; i++)
        fin >> c[i];

    c[k] = n;
    for(int i = 1;i <= m; i++)
    {
        fin >> x >> y >> z;
        v[x].push_back({y,z});
        v[y].push_back({x,z});
    }
    pq.push({1,0});
    while(!pq.empty())
        {
            int a = pq.top().cost;
            int b = pq.top().nod;
            pq.pop();
            parc(a,b,1);
        }
    for(int i = 0 ; i <= k; i++)
    {
        pq.push({c[i], 0});
        while(!pq.empty())
        {
            int a = pq.top().cost;
            int b = pq.top().nod;
            pq.pop();
            parc(a,b,c[i]);
        }
    }


    for(int i = 0; i < 1 << (k + 1); i++)
        for(int j = 0 ; j <= k; j++)
            dp[i][j] = INF;

    for(int i = 0; i <= k; i++)
        dp[(1 << i)][i] = cst[c[i]][1];

    for(int i = 1; i < 1 << (k + 1); i++)
        for(int j = 0 ; j <= k; j++)
        {
            int ii = i & ~(1 << j);
            if(i != ii)
                for(int jj = 0 ; jj <= k; jj++)
                    dp[i][j] = min(1LL * dp[i][j], 1LL * dp[ii][jj] + cst[c[jj]][c[j]]);
        }
    for(int i = 0 ; i <= k; i++)
        ans = min(ans, dp[(1 << (k + 1)) - 1][i] + cst[c[i]][n]);
    fout << ans;
    return 0;
}