typedef long long ll;
typedef long double ld;
#include <bits/stdc++.h>
using namespace std;
#define int long long

signed main(){
    ll n,m,k;
    std::cin >> n>>m>>k;
    map<ll,bool> r;
    set<ll> ed;
    vector<tuple<ll,ll,ll>> rr;
    ed.insert(0);
    ed.insert(n-1);
    for (int i = 0; i < k; i++) {
        ll tmp;
        std::cin >> tmp;
        tmp--;
        r[tmp] = true;
    }
    
    vector<vector<tuple<ll,ll>>> edges(n);
    for (int i = 0; i < m; i++) {
        ll a,b,c;
        std::cin >> a>>b>>c;
        a--;b--;
        edges[a].push_back({b, c});
        edges[b].push_back({a, c});
        if(r[i]){
            ed.insert(a);
            ed.insert(b);
            rr.push_back({a,b,c});
        }
    }
    map<ll,vector<ll>> d;
    for (auto st : ed) {
        auto &dn = d[st];
        dn.resize(n,1e18);
        dn[st] = 0;
        priority_queue<pair<ll,ll>,vector<pair<ll,ll>>,greater<pair<ll,ll>>> pq;
        pq.push({0, st});
        while(!pq.empty()){
            auto [dis, pos] = pq.top();pq.pop();
            if(dn[pos]<dis)continue;
            for (auto e : edges[pos]) {
                auto [v, c] = e;
                if(dn[v]>dis+c){
                    dn[v] = dis+c;
                    pq.push({dn[v],v});
                }
            }
        }
    }
    vector<vector<vector<ll>>> dp(1<<k, vector<vector<ll>>(ed.size(), vector<ll>(ed.size(), 1e18)));
    dp[0][0][0] = 0;
    ll cntt = 0;
    map<ll,ll> con,con2;
    for (auto e : ed) {
        con[e] = cntt;
        con2[cntt] = e;
        cntt++;
    }
    
    for (int i = 0; i < (1<<k); i++) {
        for (int j = 0; j < ed.size(); j++) {
            for (int l = 0; l < ed.size(); l++) {
                for (int bit = 0; bit < k; bit++) {
                    if(i>>bit&1){
                        auto [a,b,c] = rr[bit];
                        dp[i][j][l] = min(dp[i][j][l], dp[i&~(1<<bit)][j][con[a]]+d[b][con2[l]]+c);
                        dp[i][j][l] = min(dp[i][j][l], dp[i&~(1<<bit)][j][con[b]]+d[a][con2[l]]+c);
                    }
                }
            }
        }
    }
    std::cout << dp[(1<<k)-1][0][ed.size()-1]<< std::endl;
}