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<HashMap<Integer, Integer>> graph = new ArrayList<>();
        for (int i = 0; i < n; i++) {
            graph.add(new HashMap<>());
        }
        HashMap<Integer, Integer> compress = new HashMap<>();
        int[] lefts = new int[k];
        int[] rights = new int[k];
        int[] values = new int[k];
        for (int i = 0; i < m; i++) {
            int a = sc.nextInt() - 1;
            int b = sc.nextInt() - 1;
            int c = sc.nextInt();
            if (idxes.containsKey(i)) {
                int x = idxes.get(i);
                lefts[x] = a;
                rights[x] = b;
                values[x] = c;
                compress.put(a, null);
                compress.put(b, null);
            } else {
                graph.get(a).put(b, c);
                graph.get(b).put(a, c);
            }
        }
        compress.put(0, null);
        compress.put(n - 1, null);
        int count = 0;
        int[] cities = new int[compress.size()];
        for (int x : compress.keySet()) {
            cities[count] = x;
            compress.put(x, count++);
        }
        PriorityQueue<Path> queue = new PriorityQueue<>();
        int[][] cost = new int[count][n];
        for (int i = 0; i < count; i++) {
            Arrays.fill(cost[i], Integer.MAX_VALUE);
            queue.add(new Path(cities[i], 0));
            while (queue.size() > 0) {
                Path p = queue.poll();
                if (cost[i][p.idx] <= p.value) {
                    continue;
                }
                cost[i][p.idx] = p.value;
                for (int x : graph.get(p.idx).keySet()) {
                    queue.add(new Path(x, p.value + graph.get(p.idx).get(x)));
                }
            }
        }
        ArrayList<ArrayList<Road>> small = new ArrayList<>();
        for (int i = 0; i < count; i++) {
            small.add(new ArrayList<>());
        }
        for (int i = 0; i < count; i++) {
            for (int j = 0; j < count; j++) {
                if (i == j) {
                    continue;
                }
                small.get(i).add(new Road(j, cost[i][cities[j]], -1));
            }
        }
        for (int i = 0; i < k; i++) {
            small.get(compress.get(lefts[i])).add(new Road(compress.get(rights[i]), values[i], i));
            small.get(compress.get(rights[i])).add(new Road(compress.get(lefts[i]), values[i], i));
        }
        long[][] ans = new long[1 << k][count];
        for (long[] arr : ans) {
            Arrays.fill(arr, Long.MAX_VALUE);
        }
        PriorityQueue<Road> roads = new PriorityQueue<>();
        roads.add(new Road(compress.get(0), 0, 0));
        while (roads.size() > 0) {
            Road r = roads.poll();
            if (ans[r.mask][r.idx] <= r.value) {
                continue;
            }
            for (int i = r.mask; i > 0; i = (r.mask & (i - 1))) {
                ans[i][r.idx] = Math.min(ans[i][r.idx], r.value);
            }
            ans[0][r.idx] = Math.min(ans[0][r.idx], r.value);
            for (Road x : small.get(r.idx)) {
                if (x.mask >= 0) {
                    roads.add(new Road(x.idx, r.value + x.value, r.mask | (1 << x.mask)));
                } else {
                    roads.add(new Road(x.idx, r.value + x.value, r.mask));
                }
            }
        }
        System.out.println(ans[(1 << k) - 1][compress.get(n - 1)]);
    }
    
    static class Path implements Comparable<Path> {
        int idx;
        int value;

        public Path(int idx, int value)  {
            this.idx = idx;
            this.value = value;
        }
        
        public int compareTo(Path another) {
            return value - another.value;
        }
    }
    
    static class Road implements Comparable<Road> {
        int idx;
        long value;
        int mask;
        
        public Road(int idx, long value, int mask) {
            this.idx = idx;
            this.value = value;
            this.mask = mask;
        }
        
        public int compareTo(Road another) {
            if (value == another.value) {
                return 0;
            } else if (value < another.value) {
                return -1;
            } else {
                return 1;
            }
        }
    }
}

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();
    }
}