import java.io.*;
import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner();
        int n = sc.nextInt();
        int m = sc.nextInt();
        int k = sc.nextInt();
        HashMap<Integer, Integer> idxes = new HashMap<>();
        for (int i = 0; i < k; i++) {
            idxes.put(sc.nextInt() - 1, i);
        }
        ArrayList<ArrayList<Road>> graph = new ArrayList<>();
        for (int i = 0; i < n; i++) {
            graph.add(new ArrayList<>());
        }
        for (int i = 0; i < m; i++) {
            int a = sc.nextInt() - 1;
            int b = sc.nextInt() - 1;
            int c = sc.nextInt();
            graph.get(a).add(new Road(b, c, idxes.getOrDefault(i, -1)));
            graph.get(b).add(new Road(a, c, idxes.getOrDefault(i, -1)));
        }
        PriorityQueue<Path> queue = new PriorityQueue<>();
        queue.add(new Path(0, 0, 0));
        int[][] cost = new int[1 << k][n];
        for (int[] arr : cost) {
            Arrays.fill(arr, Integer.MAX_VALUE);
        }
        while (queue.size() > 0) {
            Path p = queue.poll();
            if (cost[p.mask][p.idx] <= p.value) {
                continue;
            }
            cost[p.mask][p.idx] = p.value;
            for (Road x : graph.get(p.idx)) {
                if (x.mask >= 0) {
                    queue.add(new Path(x.idx, p.value + x.cost, p.mask | (1 << x.mask)));
                } else {
                    queue.add(new Path(x.idx, p.value + x.cost, p.mask));
                }
            }
        }
        System.out.println(cost[(1 << k) - 1][n - 1]);
    }
    
    static class Path implements Comparable<Path> {
        int idx;
        int value;
        int mask;
        
        public Path(int idx, int value, int mask)  {
            this.idx = idx;
            this.value = value;
            this.mask = mask;
        }
        
        public int compareTo(Path another) {
            return value - another.value;
        }
    }
    
    static class Road {
        int idx;
        int cost;
        int mask;
        
        public Road(int idx, int cost, int mask) {
            this.idx = idx;
            this.cost = cost;
            this.mask = mask;
        }
    }
}

class Scanner {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    StringTokenizer st = new StringTokenizer("");
    
    public Scanner() throws Exception {
        
    }
    
    public int nextInt() throws Exception {
        return Integer.parseInt(next());
    }
    
    public long nextLong() throws Exception {
        return Long.parseLong(next());
    }
    
    public double nextDouble() throws Exception {
        return Double.parseDouble(next());
    }
    
    public String next() throws Exception {
        if (!st.hasMoreTokens()) {
            st = new StringTokenizer(br.readLine());
        }
        return st.nextToken();
    }
}