#include <bits/stdc++.h>

using namespace std;
const int nmax=2005;
struct lista
{
    int v,cost;
};
struct coada
{
    int nod,cost;
    bool operator < (const coada &x) const
    {
        return cost > x.cost;
    }
};
int m, n, k;
int cost[nmax][nmax],dp[35000][20];
vector<lista>l[nmax];
priority_queue<coada>pq;
int sol[nmax];
int s[nmax];
void dijkstra(int nod)
{
    for(int i = 1 ; i <= n ; i ++)
        sol[i] = INT_MAX;
    coada temp;
    temp.nod = nod;
    temp.cost = 0;
    pq.push(temp);
    while(!pq.empty())
    {
        temp = pq.top();
        int val = temp.nod;
        int cst = temp.cost;
        pq.pop();
        if(sol[val] != INT_MAX)
            continue;
        sol[temp.nod] = cst;

        for(vector<lista>::iterator it = l[val].begin() ; it != l[val].end() ; it++)
        {
            lista temp1 = *it;
            coada aux;
            aux.nod = temp1.v;
            aux.cost = temp1.cost + cst;
            pq.push(aux);
        }
    }

    for(int i = 1 ; i <= n ; i++)
    {
        if(sol[i] == nod)
            continue;
        if(sol[i] == INT_MAX)
            cost[i][nod] = cost[nod][i] = 0;
        else
            cost[i][nod] = cost[nod][i] = sol[i];
    }
}

void dinamica()
{
    for(int i = 1 ; i <= k ; i++)
        dp[1<<(i-1)][i] = cost[1][s[i]];
    int ns = 1<<k;
    for(int xz = 0 ; xz < ns ; xz++)
    {
        for(int i = 1 ; i <= k ; i++)
            if(xz & (1<<(i-1)) && xz != (1<<(i-1)))
            {
                dp[xz][i] = INT_MAX;
                for(int j = 1 ; j <= k ; j++)
                {
                    if(i != j && xz & (1 << (j-1)))
                        dp[xz][i] = min(dp[xz][i],dp[xz-(1<<(i-1))][j]+cost[s[j]][s[i]]);
                }

            }
    }
}

int main()
{
    ifstream cin("ubuntzei.in");
    ofstream cout("ubuntzei.out");
    int u, v, c;
    cin>>n>>m>>k;
    for(int i = 1 ; i <= k ; i++)
        cin>>s[i];
    s[0] = 1;
    s[++k] = n;
    for(int i = 1 ; i <= m ; i++)
    {
        cin>>u>>v>>c;
        lista temp;
        temp.cost = c;
        temp.v = v;
        l[u].push_back(temp);
        temp.cost = c;
        temp.v = u;
        l[v].push_back(temp);
    }
    for(int i = 0 ; i <= k ; i++)
        dijkstra(s[i]);
    dinamica();
    int ans = INT_MAX;
    int ns = 1<<k;
    for(int i = 1 ; i <= k ; i++)
        ans = min(ans,dp[ns-1][i]+cost[s[i]][n]);
    cout<<ans;
    return 0;
}