#include <cstdio>
#include <queue>
#include <vector>
using namespace std;
const int NMAX = 2000;
struct oras
{
    int x, config, dist;
};oras aux;
struct drum
{
    int x, dist;
};drum nou;
class MyCmp
{
    public:
        bool operator ()(const oras &a, const oras &b)
        {
            if (a.dist == b.dist)
                return a.config > b.config;
            return a.dist > b.dist;
        }
};
priority_queue <oras, vector<oras>, MyCmp> pq;
vector <drum> g[NMAX + 5];
bool viz[NMAX + 5][33000];
int ok[NMAX + 5];
int main()
{
    freopen("ubuntzei.in", "r", stdin);
    freopen("ubuntzei.out", "w", stdout);
    int n, m, k, x, y, config, dist;
    scanf("%d %d %d", &n, &m, &k);
    for (int i = 1; i <= n; ++i)
        ok[i] = -1;
    for (int i = 0; i < k; ++i)
        scanf("%d", &x), ok[x] = i;
    for (int i = 1; i <= m; ++i)
    {
        scanf("%d %d %d", &x, &y, &dist);
        nou.dist = dist;
        nou.x = y; g[x].push_back(nou);
        nou.x = x; g[y].push_back(nou);
    }
    aux.config = 0; aux.x = 1; aux.dist = 0;
    pq.push(aux);
    while (!pq.empty())
    {
        x = pq.top().x;
        config = pq.top().config;
        dist = pq.top().dist;
        pq.pop();

        if (viz[x][config] == 1)
            continue;
        viz[x][config] = 1;
        if (x == n && config == ((1 << k) - 1))
        {
            printf("%d\n", dist);
            return 0;
        }
        for (int i = 0; i < g[x].size(); ++i)
        {
            aux.x = g[x][i].x;
            aux.dist = dist + g[x][i].dist;
            aux.config = config;
            if (ok[aux.x] != -1 && ((1 << ok[aux.x]) & config) == 0)
                aux.config += (1 << ok[aux.x]);
            if (viz[aux.x][aux.config] == 0)
                pq.push(aux);
        }
    }
    return 0;
}