#include <bits/stdc++.h>
#define inf 1073741823
using namespace std;
using ll = long long;
using Pair = pair<int, int>;


vector<int> dijkstra(int sv, vector<vector<Pair> >& graph, int N){
    vector<int> dp(N, inf);
    priority_queue<Pair, vector<Pair>, greater<Pair> > pq = {};
    pq.push({0, sv});
    while(!pq.empty()){
        auto[d, v] = pq.top();  pq.pop();
        if(dp[v] <= d){
            continue;
        }
        dp[v] = d;
        for(auto&[nv, nd] : graph[v]){
            pq.push({d + nd, nv});
        }
    }
    return dp;
}


int main(){
    int N, M, K;    cin >> N >> M >> K;
    vector<int> R(K);
    for(auto& x : R){
        cin >> x;   --x;
    }
    vector<vector<int> > edges(M);
    vector<vector<Pair> > graph(N, vector<Pair>({}));
    for(int i = 0; i < M; ++i){
        int x, y, z;    cin >> x >> y >> z;
        --x, --y;
        edges[i] = {x, y, z};
        graph[x].push_back({y, z});
        graph[y].push_back({x, z});
    }

    unordered_set<int> V = {};
    V.insert(0), V.insert(N - 1);
    for(auto r : R){
        V.insert(edges[r][0]);
        V.insert(edges[r][1]);
    }
    vector<vector<int> > dist(N, vector<int>({}));
    for(auto& sv : V){
        dist[sv] = dijkstra(sv, graph, N);
    }

    vector<vector<vector<int> > > dp(1 << K, vector<vector<int> >(K, vector<int>(2, inf)));
    for(int i = 0; i < K; ++i){
        for(int j = 0; j < 2; ++j){
            dp[1 << i][i][j] = dist[0][edges[R[i]][j ^ 1]] + edges[R[i]][2];
        }
    }
    for(int bit = 1; bit < (1 << K); ++bit){
        for(int s = 0; s < K; ++s){
            if((bit & (1 << s)) == 0){
                continue;
            }
            for(int t = 0; t < K; ++t){
                if(bit & (1 << t)){
                    continue;
                }
                int nbit = bit | (1 << t);
                int c = edges[R[t]][2];
                for(int x = 0; x < 2; ++x){
                    for(int y = 0; y < 2; ++y){
                        int p = edges[R[s]][x], q = edges[R[t]][y ^ 1];
                        int d = dp[bit][s][x] + dist[p][q] + c;
                        if(dp[nbit][t][y] <= d){
                            continue;
                        }
                        dp[nbit][t][y] = d;
                    }
                }
            }
        }
    }

    int ans = inf;
    for(int i = 0; i < K; ++i){
        for(int j = 0; j < 2; ++j){
            int d = dp[(1 << K) - 1][i][j] + dist[edges[R[i]][j]][N - 1];
            if(ans <= d){
                continue;
            }
            ans = d;
        }
    }
    cout << ans << endl;

    return 0;
}